diff --git a/src/Appwrite/GraphQL/Types/Mapper.php b/src/Appwrite/GraphQL/Types/Mapper.php
index 3c7915bc96..db330034b3 100644
--- a/src/Appwrite/GraphQL/Types/Mapper.php
+++ b/src/Appwrite/GraphQL/Types/Mapper.php
@@ -226,7 +226,7 @@ class Mapper
             ];
 
             if (!$rule['required']) {
-                $fields[$escapedKey]['defaultValue'] = $rule['default'];
+                $fields[$escapedKey]['defaultValue'] = $rule['default'] ?? '';
             }
         }