public function isSendError()
    {
        $message = $this->getOriginalMessageObject();
        $headers = $message->getHeaders();
        $isSendError = false;
        if (is_array($headers) && count($headers)) {
            foreach (array_keys($headers) as $key) {
                if (strstr($key, 'x-fail') !== false) {
                    $isSendError = true;
                    break;
                }
            }
        }

        return $isSendError;
    }