update: fix switch payment handling fee calc

app/Http/Controllers/User/OrderController.php

@@ -191,6 +191,7 @@ class OrderController extends Controller
         $payment = Payment::find($method);
         if (!$payment || $payment->enable !== 1) abort(500, __('Payment method is not available'));
         $paymentService = new PaymentService($payment->payment, $payment->id);
+        $order->handling_amount = NULL;
         if ($payment->handling_fee_fixed || $payment->handling_fee_percent) {
             $order->handling_amount = round(($order->total_amount * ($payment->handling_fee_percent / 100)) + $payment->handling_fee_fixed);
         }