fix: check of possible undefined save method

src/QUI/ERP/Coupons/Events.php

@@ -27,6 +27,7 @@
 use function is_string;
 use function json_decode;
 use function json_encode;
+use function method_exists;
 
 /**
  * Class Events
@@ -213,7 +214,9 @@ public static function onQuiqqerOrderBasketRemovePos(
             $Order->setData('quiqqer-coupons', $orderCoupons);
 
             try {
-                $Order->save();
+                if (method_exists($Order, 'save')) {
+                    $Order->save();
+                }
             } catch (QUI\Exception) {
             }
         }