Odoo Error, a partner cannot follow twice the same object
I have receiving this odoo error when I try to duplicate a set of record. I have inherited
['mail.thread', 'ir.needaction_mixin'] in the current class. I didn't found any solution online or myself or from odoo. Still stuck here around for 2 days.
Anybody have any idea on this ? Currently I'm using Odoo 10.
Thanks & Regards in advance.