diff --git a/galette/lib/Galette/Entity/Contribution.php b/galette/lib/Galette/Entity/Contribution.php
index 940b8c79d..aa9c1ce41 100644
--- a/galette/lib/Galette/Entity/Contribution.php
+++ b/galette/lib/Galette/Entity/Contribution.php
@@ -567,7 +567,7 @@ public function checkOverlap(): bool|string
                 'c.' . ContributionsTypes::PK . '=ct.' . ContributionsTypes::PK,
                 array()
             )->where([Adherent::PK => $this->member])
-                ->where->notEqualTo('cotis_extension', 0)
+                ->where->notEqualTo('cotis_extension', ContributionsTypes::TYPE_DONATION)
                 ->where->nest->nest
                 ->greaterThanOrEqualTo('date_debut_cotis', $this->begin_date)
                 ->lessThanOrEqualTo('date_debut_cotis', $this->end_date)
@@ -865,7 +865,7 @@ public static function getDueDate(Db $zdb, ?int $member_id): ?string
             )->where(
                 [Adherent::PK => $member_id]
             )
-            ->where->notEqualTo('cotis_extension', 0);
+            ->where->notEqualTo('cotis_extension', ContributionsTypes::TYPE_DONATION);
 
             $results = $zdb->execute($select);
             $result = $results->current();