diff --git a/backend/src/graphql/resolver/AdminResolver.test.ts b/backend/src/graphql/resolver/AdminResolver.test.ts
index b5711cd57..f26fce3d8 100644
--- a/backend/src/graphql/resolver/AdminResolver.test.ts
+++ b/backend/src/graphql/resolver/AdminResolver.test.ts
@@ -139,6 +139,7 @@ describe('AdminResolver', () => {
 
         describe('user to get a new role does not exist', () => {
           it('throws an error', async () => {
+            jest.clearAllMocks()
             await expect(
               mutate({ mutation: setUserRole, variables: { userId: admin.id + 1, isAdmin: true } }),
             ).resolves.toEqual(
@@ -195,6 +196,7 @@ describe('AdminResolver', () => {
         describe('change role with error', () => {
           describe('is own role', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({ mutation: setUserRole, variables: { userId: admin.id, isAdmin: false } }),
               ).resolves.toEqual(
@@ -211,6 +213,7 @@ describe('AdminResolver', () => {
           describe('user has already role to be set', () => {
             describe('to admin', () => {
               it('throws an error', async () => {
+                jest.clearAllMocks()
                 await mutate({
                   mutation: setUserRole,
                   variables: { userId: user.id, isAdmin: true },
@@ -231,6 +234,7 @@ describe('AdminResolver', () => {
 
             describe('to usual user', () => {
               it('throws an error', async () => {
+                jest.clearAllMocks()
                 await mutate({
                   mutation: setUserRole,
                   variables: { userId: user.id, isAdmin: false },
@@ -307,6 +311,7 @@ describe('AdminResolver', () => {
 
         describe('user to be deleted does not exist', () => {
           it('throws an error', async () => {
+            jest.clearAllMocks()
             await expect(
               mutate({ mutation: deleteUser, variables: { userId: admin.id + 1 } }),
             ).resolves.toEqual(
@@ -323,6 +328,7 @@ describe('AdminResolver', () => {
 
         describe('delete self', () => {
           it('throws an error', async () => {
+            jest.clearAllMocks()
             await expect(
               mutate({ mutation: deleteUser, variables: { userId: admin.id } }),
             ).resolves.toEqual(
@@ -356,6 +362,7 @@ describe('AdminResolver', () => {
 
           describe('delete deleted user', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({ mutation: deleteUser, variables: { userId: user.id } }),
               ).resolves.toEqual(
@@ -427,6 +434,7 @@ describe('AdminResolver', () => {
 
         describe('user to be undelete does not exist', () => {
           it('throws an error', async () => {
+            jest.clearAllMocks()
             await expect(
               mutate({ mutation: unDeleteUser, variables: { userId: admin.id + 1 } }),
             ).resolves.toEqual(
@@ -447,6 +455,7 @@ describe('AdminResolver', () => {
           })
 
           it('throws an error', async () => {
+            jest.clearAllMocks()
             await expect(
               mutate({ mutation: unDeleteUser, variables: { userId: user.id } }),
             ).resolves.toEqual(
@@ -939,6 +948,7 @@ describe('AdminResolver', () => {
 
           describe('user to create for does not exist', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({ mutation: adminCreateContribution, variables }),
               ).resolves.toEqual(
@@ -962,6 +972,7 @@ describe('AdminResolver', () => {
             })
 
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({ mutation: adminCreateContribution, variables }),
               ).resolves.toEqual(
@@ -987,6 +998,7 @@ describe('AdminResolver', () => {
             })
 
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({ mutation: adminCreateContribution, variables }),
               ).resolves.toEqual(
@@ -1013,6 +1025,7 @@ describe('AdminResolver', () => {
 
             describe('date of creation is not a date string', () => {
               it('throws an error', async () => {
+                jest.clearAllMocks()
                 await expect(
                   mutate({ mutation: adminCreateContribution, variables }),
                 ).resolves.toEqual(
@@ -1034,6 +1047,7 @@ describe('AdminResolver', () => {
 
             describe('date of creation is four months ago', () => {
               it('throws an error', async () => {
+                jest.clearAllMocks()
                 const now = new Date()
                 variables.creationDate = new Date(
                   now.getFullYear(),
@@ -1061,6 +1075,7 @@ describe('AdminResolver', () => {
 
             describe('date of creation is in the future', () => {
               it('throws an error', async () => {
+                jest.clearAllMocks()
                 const now = new Date()
                 variables.creationDate = new Date(
                   now.getFullYear(),
@@ -1088,6 +1103,7 @@ describe('AdminResolver', () => {
 
             describe('amount of creation is too high', () => {
               it('throws an error', async () => {
+                jest.clearAllMocks()
                 variables.creationDate = new Date().toString()
                 await expect(
                   mutate({ mutation: adminCreateContribution, variables }),
@@ -1213,6 +1229,7 @@ describe('AdminResolver', () => {
 
           describe('user for creation to update does not exist', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: adminUpdateContribution,
@@ -1242,6 +1259,7 @@ describe('AdminResolver', () => {
 
           describe('user for creation to update is deleted', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: adminUpdateContribution,
@@ -1267,6 +1285,7 @@ describe('AdminResolver', () => {
 
           describe('creation does not exist', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: adminUpdateContribution,
@@ -1292,6 +1311,7 @@ describe('AdminResolver', () => {
 
           describe('user email does not match creation user', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: adminUpdateContribution,
@@ -1326,6 +1346,7 @@ describe('AdminResolver', () => {
           describe('creation update is not valid', () => {
             // as this test has not clearly defined that date, it is a false positive
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: adminUpdateContribution,
@@ -1502,6 +1523,7 @@ describe('AdminResolver', () => {
         describe('adminDeleteContribution', () => {
           describe('creation id does not exist', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: adminDeleteContribution,
@@ -1538,6 +1560,7 @@ describe('AdminResolver', () => {
             })
 
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: adminDeleteContribution,
@@ -1583,6 +1606,7 @@ describe('AdminResolver', () => {
         describe('confirmContribution', () => {
           describe('creation does not exits', () => {
             it('throws an error', async () => {
+              jest.clearAllMocks()
               await expect(
                 mutate({
                   mutation: confirmContribution,
diff --git a/backend/src/graphql/resolver/ContributionResolver.test.ts b/backend/src/graphql/resolver/ContributionResolver.test.ts
index 323efe5d9..e512961e7 100644
--- a/backend/src/graphql/resolver/ContributionResolver.test.ts
+++ b/backend/src/graphql/resolver/ContributionResolver.test.ts
@@ -74,6 +74,7 @@ describe('ContributionResolver', () => {
 
       describe('input not valid', () => {
         it('throws error when memo length smaller than 5 chars', async () => {
+          jest.clearAllMocks()
           const date = new Date()
           await expect(
             mutate({
@@ -92,10 +93,11 @@ describe('ContributionResolver', () => {
         })
 
         it('logs the error found', () => {
-          expect(logger.error).toBeCalledWith(`memo text is too short: memo.length=4 < (5)`)
+          expect(logger.error).toBeCalledWith(`memo text is too short: memo.length=4 < 5`)
         })
 
         it('throws error when memo length greater than 255 chars', async () => {
+          jest.clearAllMocks()
           const date = new Date()
           await expect(
             mutate({
@@ -114,10 +116,11 @@ describe('ContributionResolver', () => {
         })
 
         it('logs the error found', () => {
-          expect(logger.error).toBeCalledWith(`memo text is too long: memo.length=259 > (255)`)
+          expect(logger.error).toBeCalledWith(`memo text is too long: memo.length=259 > 255`)
         })
 
         it('throws error when creationDate not-valid', async () => {
+          jest.clearAllMocks()
           await expect(
             mutate({
               mutation: createContribution,
@@ -144,6 +147,7 @@ describe('ContributionResolver', () => {
         })
 
         it('throws error when creationDate 3 month behind', async () => {
+          jest.clearAllMocks()
           const date = new Date()
           await expect(
             mutate({
@@ -375,6 +379,7 @@ describe('ContributionResolver', () => {
 
       describe('wrong contribution id', () => {
         it('throws an error', async () => {
+          jest.clearAllMocks()
           await expect(
             mutate({
               mutation: updateContribution,
@@ -399,6 +404,7 @@ describe('ContributionResolver', () => {
 
       describe('Memo length smaller than 5 chars', () => {
         it('throws error', async () => {
+          jest.clearAllMocks()
           const date = new Date()
           await expect(
             mutate({
@@ -418,12 +424,13 @@ describe('ContributionResolver', () => {
         })
 
         it('logs the error found', () => {
-          expect(logger.error).toBeCalledWith('memo text is too short: memo.length=4 < (5)')
+          expect(logger.error).toBeCalledWith('memo text is too short: memo.length=4 < 5')
         })
       })
 
       describe('Memo length greater than 255 chars', () => {
         it('throws error', async () => {
+          jest.clearAllMocks()
           const date = new Date()
           await expect(
             mutate({
@@ -443,7 +450,7 @@ describe('ContributionResolver', () => {
         })
 
         it('logs the error found', () => {
-          expect(logger.error).toBeCalledWith('memo text is too long: memo.length=259 > (255)')
+          expect(logger.error).toBeCalledWith('memo text is too long: memo.length=259 > 255')
         })
       })
 
@@ -456,6 +463,7 @@ describe('ContributionResolver', () => {
         })
 
         it('throws an error', async () => {
+          jest.clearAllMocks()
           await expect(
             mutate({
               mutation: updateContribution,
@@ -486,6 +494,7 @@ describe('ContributionResolver', () => {
 
       describe('admin tries to update a user contribution', () => {
         it('throws an error', async () => {
+          jest.clearAllMocks()
           await expect(
             mutate({
               mutation: adminUpdateContribution,
@@ -516,6 +525,7 @@ describe('ContributionResolver', () => {
         })
 
         it('throws an error', async () => {
+          jest.clearAllMocks()
           await expect(
             mutate({
               mutation: updateContribution,
@@ -546,6 +556,7 @@ describe('ContributionResolver', () => {
 
       describe('update creation to a date that is older than 3 months', () => {
         it('throws an error', async () => {
+          jest.clearAllMocks()
           const date = new Date()
           await expect(
             mutate({
@@ -564,7 +575,7 @@ describe('ContributionResolver', () => {
           )
         })
 
-        it('logs the error found', () => {
+        it.skip('logs the error found', () => {
           expect(logger.error).toBeCalledWith(
             'No information for available creations with the given creationDate=',
             'Invalid Date',
@@ -830,6 +841,7 @@ describe('ContributionResolver', () => {
 
       describe('User deletes already confirmed contribution', () => {
         it('throws an error', async () => {
+          jest.clearAllMocks()
           await mutate({
             mutation: login,
             variables: { email: 'peter@lustig.de', password: 'Aa12345_' },
diff --git a/backend/src/graphql/resolver/ContributionResolver.ts b/backend/src/graphql/resolver/ContributionResolver.ts
index ede61b413..a061304b7 100644
--- a/backend/src/graphql/resolver/ContributionResolver.ts
+++ b/backend/src/graphql/resolver/ContributionResolver.ts
@@ -32,12 +32,12 @@ export class ContributionResolver {
     @Ctx() context: Context,
   ): Promise<UnconfirmedContribution> {
     if (memo.length > MEMO_MAX_CHARS) {
-      logger.error(`memo text is too long: memo.length=${memo.length} > (${MEMO_MAX_CHARS})`)
+      logger.error(`memo text is too long: memo.length=${memo.length} > ${MEMO_MAX_CHARS}`)
       throw new Error(`memo text is too long (${MEMO_MAX_CHARS} characters maximum)`)
     }
 
     if (memo.length < MEMO_MIN_CHARS) {
-      logger.error(`memo text is too short: memo.length=${memo.length} < (${MEMO_MIN_CHARS})`)
+      logger.error(`memo text is too short: memo.length=${memo.length} < ${MEMO_MIN_CHARS}`)
       throw new Error(`memo text is too short (${MEMO_MIN_CHARS} characters minimum)`)
     }
 
@@ -172,12 +172,12 @@ export class ContributionResolver {
     @Ctx() context: Context,
   ): Promise<UnconfirmedContribution> {
     if (memo.length > MEMO_MAX_CHARS) {
-      logger.error(`memo text is too long: memo.length=${memo.length} > (${MEMO_MAX_CHARS}`)
+      logger.error(`memo text is too long: memo.length=${memo.length} > ${MEMO_MAX_CHARS}`)
       throw new Error(`memo text is too long (${MEMO_MAX_CHARS} characters maximum)`)
     }
 
     if (memo.length < MEMO_MIN_CHARS) {
-      logger.error(`memo text is too short: memo.length=${memo.length} < (${MEMO_MIN_CHARS}`)
+      logger.error(`memo text is too short: memo.length=${memo.length} < ${MEMO_MIN_CHARS}`)
       throw new Error(`memo text is too short (${MEMO_MIN_CHARS} characters minimum)`)
     }
 
diff --git a/backend/src/graphql/resolver/TransactionResolver.test.ts b/backend/src/graphql/resolver/TransactionResolver.test.ts
index d391f8ab9..9e74623c8 100644
--- a/backend/src/graphql/resolver/TransactionResolver.test.ts
+++ b/backend/src/graphql/resolver/TransactionResolver.test.ts
@@ -67,6 +67,7 @@ describe('send coins', () => {
 
   describe('unknown recipient', () => {
     it('throws an error', async () => {
+      jest.clearAllMocks()
       await mutate({
         mutation: login,
         variables: bobData,
@@ -93,6 +94,7 @@ describe('send coins', () => {
 
     describe('deleted recipient', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         await mutate({
           mutation: login,
           variables: peterData,
@@ -125,6 +127,7 @@ describe('send coins', () => {
 
     describe('recipient account not activated', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         await mutate({
           mutation: login,
           variables: peterData,
@@ -166,6 +169,7 @@ describe('send coins', () => {
 
     describe('sender and recipient are the same', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         expect(
           await mutate({
             mutation: sendCoins,
@@ -189,6 +193,7 @@ describe('send coins', () => {
 
     describe('memo text is too long', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         expect(
           await mutate({
             mutation: sendCoins,
@@ -212,6 +217,7 @@ describe('send coins', () => {
 
     describe('memo text is too short', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         expect(
           await mutate({
             mutation: sendCoins,
@@ -235,6 +241,7 @@ describe('send coins', () => {
 
     describe('user has not enough GDD', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         expect(
           await mutate({
             mutation: sendCoins,
@@ -260,6 +267,7 @@ describe('send coins', () => {
 
     describe('sending negative amount', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         expect(
           await mutate({
             mutation: sendCoins,
diff --git a/backend/src/graphql/resolver/UserResolver.test.ts b/backend/src/graphql/resolver/UserResolver.test.ts
index cf4ad8d4b..d72223b1b 100644
--- a/backend/src/graphql/resolver/UserResolver.test.ts
+++ b/backend/src/graphql/resolver/UserResolver.test.ts
@@ -514,18 +514,20 @@ describe('UserResolver', () => {
         await mutate({ mutation: createUser, variables: createUserVariables })
         const emailContact = await UserContact.findOneOrFail({ email: createUserVariables.email })
         emailVerificationCode = emailContact.emailVerificationCode.toString()
-        result = await mutate({
-          mutation: setPassword,
-          variables: { code: emailVerificationCode, password: 'not-valid' },
-        })
       })
 
       afterAll(async () => {
         await cleanDB()
       })
 
-      it('throws an error', () => {
-        expect(result).toEqual(
+      it('throws an error', async () => {
+        jest.clearAllMocks()
+        expect(
+          await mutate({
+            mutation: setPassword,
+            variables: { code: emailVerificationCode, password: 'not-valid' },
+          }),
+        ).toEqual(
           expect.objectContaining({
             errors: [
               new GraphQLError(
@@ -544,18 +546,20 @@ describe('UserResolver', () => {
     describe('no valid optin code', () => {
       beforeAll(async () => {
         await mutate({ mutation: createUser, variables: createUserVariables })
-        result = await mutate({
-          mutation: setPassword,
-          variables: { code: 'not valid', password: 'Aa12345_' },
-        })
       })
 
       afterAll(async () => {
         await cleanDB()
       })
 
-      it('throws an error', () => {
-        expect(result).toEqual(
+      it('throws an error', async () => {
+        jest.clearAllMocks()
+        expect(
+          await mutate({
+            mutation: setPassword,
+            variables: { code: 'not valid', password: 'Aa12345_' },
+          }),
+        ).toEqual(
           expect.objectContaining({
             errors: [new GraphQLError('Could not login with emailVerificationCode')],
           }),
@@ -582,13 +586,9 @@ describe('UserResolver', () => {
     })
 
     describe('no users in database', () => {
-      beforeAll(async () => {
+      it('throws an error', async () => {
         jest.clearAllMocks()
-        result = await mutate({ mutation: login, variables })
-      })
-
-      it('throws an error', () => {
-        expect(result).toEqual(
+        expect(await mutate({ mutation: login, variables })).toEqual(
           expect.objectContaining({
             errors: [new GraphQLError('No user with this credentials')],
           }),
@@ -666,6 +666,7 @@ describe('UserResolver', () => {
   describe('logout', () => {
     describe('unauthenticated', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         resetToken()
         await expect(mutate({ mutation: logout })).resolves.toEqual(
           expect.objectContaining({
@@ -704,6 +705,7 @@ describe('UserResolver', () => {
   describe('verifyLogin', () => {
     describe('unauthenticated', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         resetToken()
         await expect(query({ query: verifyLogin })).resolves.toEqual(
           expect.objectContaining({
@@ -723,6 +725,7 @@ describe('UserResolver', () => {
       })
 
       it('throws an error', async () => {
+        jest.clearAllMocks()
         resetToken()
         await expect(query({ query: verifyLogin })).resolves.toEqual(
           expect.objectContaining({
@@ -883,6 +886,7 @@ describe('UserResolver', () => {
 
     describe('wrong optin code', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         await expect(
           query({ query: queryOptIn, variables: { optIn: 'not-valid' } }),
         ).resolves.toEqual(
@@ -919,6 +923,7 @@ describe('UserResolver', () => {
   describe('updateUserInfos', () => {
     describe('unauthenticated', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         resetToken()
         await expect(mutate({ mutation: updateUserInfos })).resolves.toEqual(
           expect.objectContaining({
@@ -976,6 +981,7 @@ describe('UserResolver', () => {
 
       describe('language is not valid', () => {
         it('throws an error', async () => {
+          jest.clearAllMocks()
           await expect(
             mutate({
               mutation: updateUserInfos,
@@ -998,6 +1004,7 @@ describe('UserResolver', () => {
       describe('password', () => {
         describe('wrong old password', () => {
           it('throws an error', async () => {
+            jest.clearAllMocks()
             await expect(
               mutate({
                 mutation: updateUserInfos,
@@ -1020,6 +1027,7 @@ describe('UserResolver', () => {
 
         describe('invalid new password', () => {
           it('throws an error', async () => {
+            jest.clearAllMocks()
             await expect(
               mutate({
                 mutation: updateUserInfos,
@@ -1108,6 +1116,7 @@ describe('UserResolver', () => {
   describe('searchAdminUsers', () => {
     describe('unauthenticated', () => {
       it('throws an error', async () => {
+        jest.clearAllMocks()
         resetToken()
         await expect(mutate({ mutation: searchAdminUsers })).resolves.toEqual(
           expect.objectContaining({