protected function setCartItems($items)
    {
        return (new Collection($items))->map(function ($item, $num) {
            return [
                'L_PAYMENTREQUEST_0_NAME'.$num => $item['name'],
                'L_PAYMENTREQUEST_0_AMT'.$num  => $item['price'],
                'L_PAYMENTREQUEST_0_QTY'.$num  => isset($item['qty']) ? $item['qty'] : 1,
            ];
        })->flatMap(function ($value) {
            return $value;
        });
    }