diff --git a/infra-as-code/bicep/CRML/subscriptionAlias/subscriptionAlias.bicep b/infra-as-code/bicep/CRML/subscriptionAlias/subscriptionAlias.bicep
index 97b25f1bd..969262290 100644
--- a/infra-as-code/bicep/CRML/subscriptionAlias/subscriptionAlias.bicep
+++ b/infra-as-code/bicep/CRML/subscriptionAlias/subscriptionAlias.bicep
@@ -42,7 +42,7 @@ resource resSubscription 'Microsoft.Subscription/aliases@2021-10-01' = {
   properties: {
     additionalProperties: {
       tags: parTags
-      managementGroupId: empty(parManagementGroupId) ? 'null' : string(managementGroup(parManagementGroupId))
+      managementGroupId: empty(parManagementGroupId) ? null : managementGroup(parManagementGroupId)
       subscriptionOwnerId: empty(parSubscriptionOwnerId) ? null : parSubscriptionOwnerId
       subscriptionTenantId: parTenantId
     }