diff --git a/avm/res/db-for-my-sql/flexible-server/main.bicep b/avm/res/db-for-my-sql/flexible-server/main.bicep
index db661ce79c..323b052dd5 100644
--- a/avm/res/db-for-my-sql/flexible-server/main.bicep
+++ b/avm/res/db-for-my-sql/flexible-server/main.bicep
@@ -280,7 +280,7 @@ resource cMKGeoKeyVault 'Microsoft.KeyVault/vaults@2023-02-01' existing = if (!e
   )
 
   resource cMKKey 'keys@2023-02-01' existing = if (!empty(customerManagedKeyGeo.?keyVaultResourceId) && !empty(customerManagedKeyGeo.?keyName)) {
-    name: customerManagedKeyGeo.?keyName ?? 'dummyKey'
+    name: customerManagedKeyGeo.?keyName!
   }
 }