diff --git a/backend/src/graphql/model/ContributionMessage.ts b/backend/src/graphql/model/ContributionMessage.ts
index 478afe024..d757db136 100644
--- a/backend/src/graphql/model/ContributionMessage.ts
+++ b/backend/src/graphql/model/ContributionMessage.ts
@@ -40,7 +40,7 @@ export class ContributionMessage {
   @Field(() => Number, { nullable: true })
   userId: number | null
 
-  @Field(() => Boolean, { nullable: true })
+  @Field(() => Boolean)
   isModerator: boolean
 }
 @ObjectType()