diff --git a/app/system/backend/sync_router.py b/app/system/backend/sync_router.py
index 2e16835..095dd55 100644
--- a/app/system/backend/sync_router.py
+++ b/app/system/backend/sync_router.py
@@ -283,6 +283,11 @@ async def sync_vtiger_contacts() -> Dict[str, Any]:
             
             # Link contact to customer if account_id exists
             account_id = contact.get('account_id')
+            
+            # Debug: Log first 10 contacts with account_id info
+            if len(contacts) < 20:  # Only log for small batches or first few
+                logger.info(f"🔍 Debug kontakt: {first_name} {last_name}, account_id={account_id}, contact_id={contact_id if 'contact_id' in locals() else 'N/A'}")
+            
             if account_id and contact_id:
                 # Find customer by vTiger account ID
                 customer = execute_query(