diff --git a/shop/models.py b/shop/models.py
index cad36f9b..90156c46 100644
--- a/shop/models.py
+++ b/shop/models.py
@@ -273,7 +273,7 @@ class Invoice(CreatedUpdatedModel):
         return 'bornhack_invoice_%s.pdf' % self.pk
 
     def regretdate(self):
-        return inv.created+timedelta(days=14)
+        return self.created+timedelta(days=14)
 
 
 class CoinifyAPIInvoice(CreatedUpdatedModel):