diff --git a/models/res_partner.py b/models/res_partner.py
index 4f88d8985f7772cb51c09712b1086990f3837709..9f21e454b87f4c323f4bf5db81a3089d0cd113c2 100644
--- a/models/res_partner.py
+++ b/models/res_partner.py
@@ -153,7 +153,7 @@ class ScopAlfrescoAdhesionPartner(models.Model):
         """
         errors = ''
         compulsory_docs = self.env['scop.adhesion.file'].search([
-            ('coop_type_id', '=', self.cooperative_form_id),
+            ('coop_type_id', '=', self.cooperative_form_id.id),
             ('is_compulsory', '=', True)
         ])
         loaded_docs = self.env['scop.adhesion.file'].\