diff --git a/account_default_draft_move/account.py b/account_default_draft_move/account.py
index 3c5bb6c8b..522945dc1 100644
--- a/account_default_draft_move/account.py
+++ b/account_default_draft_move/account.py
@@ -53,7 +53,7 @@ class AccountMove(models.Model):
         if self:
             self._cr.execute('UPDATE account_move '
                              'SET state=%s '
-                             'WHERE id IN %s', ('draft', self.ids,))
+                             'WHERE id IN %s', ('draft', tuple(self.ids)))
         return True
 
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