code: public function sendData($data)
      {
          $headers = array(
              'Content-Type' => 'text/xml; charset=utf-8',
              'SOAPAction' => 'http://www.ecocard.com/merchantAPI/Payout'
          );
  
          $httpRequest = $this->httpClient->createRequest('POST', $this->getEndpoint(), $headers, $data);
          $httpResponse = $httpRequest->send();
          $xmlResponse = $httpResponse->xml()
              ->children('http://schemas.xmlsoap.org/soap/envelope/')
              ->children('http://www.ecocard.com/merchantAPI/');
  
          if (!isset($xmlResponse->PayoutResponse)) {
              throw new InvalidResponseException('Missing element in XML response');
          }
  
          if (!isset($xmlResponse->PayoutResponse->TransactionResponse)) {
              throw new InvalidResponseException('Missing element in XML response');
          }
  
          return new FetchTransactionResponse($this, $xmlResponse->PayoutResponse->TransactionResponse);
      }
docs: Send the request with specified data
  
  @param  mixed                    $data The data to send
  @throws InvalidResponseException
  @return FetchTransactionResponse