Extended VO is Read Only

Error:
Each row in the Query Result Columns must be mapped to a unique Query Attribute in the Mapped Entity columns.

Try with below options.

1.Each row in the query result columns must be maped to a unique query attribute in the mapped entity columns(Check any attribute is Transiet).

2.Check Your Jdeveloper Version is correct?

3. Try to Create Fresh VO Extension in new WorkSpace.

Thanks,
Dilip