[fix] error invoice attribution

models/cgscop_form_coop_contribution.py

@@ -301,5 +301,6 @@ class CgscopFormCoopContribution(models.Model):
                 ("payment_state", "=", "paid"),
                 ("id", "not in", self.invoice_ids.ids),
                 ("partner_id", "=", self.partner_id.id),
+                ("formcoop_contribution_id", "=", False),
             ]
         )