Store ur_id field on res_users

models/res_users.py

@@ -12,7 +12,7 @@ class ResUsers(models.Model):
         return self.env.user.company_id.ur_id
 
     ur_id = fields.Many2one('union.regionale', compute='_compute_ur_id',
-                            string='UR')
+                            string='UR', store=True)
 
     @api.depends('company_id.ur_id')
     def _compute_ur_id(self):