diff --git a/app/Services/GiftCardService.php b/app/Services/GiftCardService.php
index c2ac339..8f14cbe 100644
--- a/app/Services/GiftCardService.php
+++ b/app/Services/GiftCardService.php
@@ -173,7 +173,7 @@ class GiftCardService
                 $userService->assignPlan(
                     $this->user,
                     $plan,
-                    $rewards['plan_validity_days'] ?? null
+                    $rewards['plan_validity_days'] ?? 0
                 );
             }
         } else {