diff --git a/schemas/attribute.py b/schemas/attribute.py
index 876e0fe..1427868 100644
--- a/schemas/attribute.py
+++ b/schemas/attribute.py
@@ -24,7 +24,7 @@ class CreateAttributeSchema(BaseSchema):
     default_value: Optional[Any]
     description: str
     type_id: int
-    select_id: Optional[int]
+    select_id: Optional[int] = None
 
 
 class AttributeSchema(CreateAttributeSchema):