Hi,

Have you done any customization or use any custom code in the system? If so please remove the same and check it.

The system will throw such an error when the value for a required field is not supplied.

If you havent used any custom codes try to reproduce the issue in runbot. If you are getting the same in runbot, please post if as issue in Odoo git repo.

If same can't be reproduced in the runbot, you can download the latest of corresponding version and check without custom code .

Thanks