diff --git a/src/Controller/CAPI/WarrantyController.php b/src/Controller/CAPI/WarrantyController.php
index cfc49226..fc9e8cd7 100644
--- a/src/Controller/CAPI/WarrantyController.php
+++ b/src/Controller/CAPI/WarrantyController.php
@@ -150,6 +150,8 @@ class WarrantyController extends APIController
     {
         $this->denyAccessUnlessGranted('warranty.register.battery', null, 'No access.');
 
+        $serial = $req->request->get('serial');
+
         // required parameters
         $params = [
             'serial',
@@ -189,7 +191,6 @@ class WarrantyController extends APIController
             return new APIResponse(false, $msg);
         }
 
-        $serial = $req->request->get('serial');
         $date_expire_string = $req->request->get('date_expire');
         $date_pur_string = $req->request->get('date_purchase');
         $warr_class = $req->request->get('warranty_class');