diff --git a/backend/src/config/index.ts b/backend/src/config/index.ts
index b94178157..0aed77583 100644
--- a/backend/src/config/index.ts
+++ b/backend/src/config/index.ts
@@ -128,8 +128,10 @@ if (
 
 const federation = {
   FEDERATION_BACKEND_SEND_ON_API: process.env.FEDERATION_BACKEND_SEND_ON_API ?? '1_0',
-  FEDERATION_VALIDATE_COMMUNITY_TIMER:
-    Number(process.env.FEDERATION_VALIDATE_COMMUNITY_TIMER) ?? 60000,
+  // ?? operator don't work here as expected
+  FEDERATION_VALIDATE_COMMUNITY_TIMER: Number(
+    process.env.FEDERATION_VALIDATE_COMMUNITY_TIMER ?? 60000,
+  ),
   FEDERATION_XCOM_SENDCOINS_ENABLED:
     process.env.FEDERATION_XCOM_SENDCOINS_ENABLED === 'true' ?? false,
   // default value for community-uuid is equal uuid of stage-3
diff --git a/backend/src/federation/validateCommunities.ts b/backend/src/federation/validateCommunities.ts
index f19d606bd..b76e22087 100644
--- a/backend/src/federation/validateCommunities.ts
+++ b/backend/src/federation/validateCommunities.ts
@@ -8,6 +8,7 @@ import { FederatedCommunityLoggingView } from '@logging/FederatedCommunityLoggin
 import { FederationClient as V1_0_FederationClient } from '@/federation/client/1_0/FederationClient'
 import { PublicCommunityInfo } from '@/federation/client/1_0/model/PublicCommunityInfo'
 import { FederationClientFactory } from '@/federation/client/FederationClientFactory'
+import { LogError } from '@/server/LogError'
 import { backendLogger as logger } from '@/server/logger'
 
 import { startCommunityAuthentication } from './authenticateCommunities'
@@ -15,6 +16,9 @@ import { PublicCommunityInfoLoggingView } from './client/1_0/logging/PublicCommu
 import { ApiVersionType } from './enum/apiVersionType'
 
 export async function startValidateCommunities(timerInterval: number): Promise<void> {
+  if (Number.isNaN(timerInterval) || timerInterval <= 0) {
+    throw new LogError('FEDERATION_VALIDATE_COMMUNITY_TIMER is not a positive number')
+  }
   logger.info(
     `Federation: startValidateCommunities loop with an interval of ${timerInterval} ms...`,
   )