diff --git a/app/Models/CheckoutAcceptance.php b/app/Models/CheckoutAcceptance.php
index 4cdc5b073..45fc6ec08 100644
--- a/app/Models/CheckoutAcceptance.php
+++ b/app/Models/CheckoutAcceptance.php
@@ -16,8 +16,12 @@ class CheckoutAcceptance extends Model
         'declined_at' => 'datetime',
     ];
 
-    // Get the mail recipient from the config
-    public function routeNotificationForMail(): string
+    /**
+     * Get the mail recipient from the config
+     *
+     * @return mixed|string|null
+     */
+    public function routeNotificationForMail()
     {
         // At this point the endpoint is the same for everything.
         //  In the future this may want to be adapted for individual notifications.