diff --git a/cotisations/utils.py b/cotisations/utils.py
index 8166b0be..f484546a 100644
--- a/cotisations/utils.py
+++ b/cotisations/utils.py
@@ -105,8 +105,8 @@ def send_mail_voucher(invoice, request=None):
         "lastname": invoice.user.surname,
         "email": invoice.user.email,
         "phone": invoice.user.telephone,
-        "date_end": invoice.get_subscription().latest("date_end").date_end_memb,
-        "date_begin": invoice.get_subscription().earliest("date_start").date_start_memb,
+        "date_end": invoice.get_subscription().latest("date_end_memb").date_end_memb,
+        "date_begin": invoice.get_subscription().earliest("date_start_memb").date_start_memb,
     }
     templatename = CotisationsOption.get_cached_value(
         "voucher_template"