Hi,

Probably you have some records in the database, which violates this constrains, ie, there will be few records in db that doesn't have a partner set in it.

If you need to remove this message from log, update existing leads in the db by setting a partner to it. Or move the required attribute you have added in the model level or to the view level.

Thanks

Hi,

There is no required or NOT NULL on crm.lead's partner_id field in Odoo default code. So you probably have custom modules changing that.

Hope it helps