diff --git a/lib/Transport/Entity/Schedule/Connection.php b/lib/Transport/Entity/Schedule/Connection.php
index 5f7691f..71b4d1d 100644
--- a/lib/Transport/Entity/Schedule/Connection.php
+++ b/lib/Transport/Entity/Schedule/Connection.php
@@ -154,7 +154,7 @@ public static function createFromJson($json, self $obj = null)
             $obj->to->platform = $json->legs[count($json->legs) - 2]->exit->track;
         }
 
-        $obj->duration = gmdate('0z\dH:i:s', $json->duration);
+        $obj->duration = gmdate('0z\dH:i:s', $json->duration ?? 0);
 
         $numberOfVehicles = 0;
         foreach ($json->legs as $leg) {