diff --git a/account_chorus_notify/models/chorus_flow.py b/account_chorus_notify/models/chorus_flow.py
index 4554f7d..fc7f96e 100644
--- a/account_chorus_notify/models/chorus_flow.py
+++ b/account_chorus_notify/models/chorus_flow.py
@@ -11,5 +11,5 @@ class ChorusFlow(models.Model):
         for flow in self:
             if flow.status == 'IN_REJETE':
                 for invoice in flow.invoice_ids:
-                    invoice.message_post(_("Chorus flow n°%s rejected.")%(flow.name,))
+                    invoice.message_post(body=_("Chorus flow n°%s rejected.")%(flow.name,))
         return res
\ No newline at end of file