public function refund($order): Collection
    {
        $this->payload = Support::filterPayload($this->payload, $order, true);

        Events::dispatch(Events::METHOD_CALLED, new Events\MethodCalled('Wechat', 'Refund', $this->gateway, $this->payload));

        return Support::requestApi(
            'secapi/pay/refund',
            $this->payload,
            true
        );
    }