diff --git a/app/Listeners/CheckoutableListener.php b/app/Listeners/CheckoutableListener.php
index b297a4f720..c1ac134fda 100644
--- a/app/Listeners/CheckoutableListener.php
+++ b/app/Listeners/CheckoutableListener.php
@@ -156,7 +156,7 @@ class CheckoutableListener
         $ccEmails = array_filter($adminCcEmailsArray);
         $mailable =  $this->getCheckinMailType($event);
         $notifiable = $this->getNotifiables($event);
-        if  ($event->checkedOutTo->locale){
+        if ($event->checkedOutTo?->locale) {
             $mailable->locale($event->checkedOutTo->locale);
         }
         // Send email notifications