Update account_payment.py

change_vat_in_partner/models/account_payment.py

@@ -8,7 +8,7 @@ class AccountPayment(models.Model):
     @api.model_create_multi
     def create(self, vals_list):
         vals = super().create(vals_list)
-        partner = self.env['account.move'].search([("name", "=", vals_list[0]["ref"])])
+        partner = self.env['account.move'].search([("name", "=", vals_list[0]["ref"])], limit=1)
         if partner:
             vals.partner_id = partner.partner_id
-        return vals
+        return vals