reply back transaction verification

Transaction verification received on my dashboard, code are here, this ia callback message , i want this call back message to reply back to payment gateway. , Please who want to start now pm me Auto-Verification of transaction successful. Cost of product is NRs. 1584 but user has paid only NRs. 1. Might be the fraud transaction! /** * Verify the transaction with eSewa * @param $url * @param $request * @return string */ protected function verifyTransaction($url, $request) { $curl = curl_init($url); curl_setopt($curl, CURLOPT_POST, true); curl_setopt($curl, CURLOPT_POSTFIELDS, $request); curl_setopt($curl, CURLOPT_RETURNTRANSFER, true); curl_setopt($curl, CURLOPT_HEADER, false); curl_setopt($curl, CURLOPT_TIMEOUT, 30); curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false); $response = curl_exec($curl); curl_close($curl); if ($this->config->get('esewa_debug')) { $this->log->write('eSewa :: IPN REQUEST: ' . $request); $this->log->write('eSewa :: IPN RESPONSE: ' . $response); } $xmlParser = new SimpleXMLElement($response); $verificationResponse = strtoupper(trim($xmlParser->response_code)); return $verificationResponse; } /** * Checks if the transaction if fraud and returns the fraud message * @param $order_info * @param $paidAmount * @return string */ protected function checkFraud($order_info, $paidAmount) { $amountToBePaid = $this->currency->format($order_info['total'], 'NPR', false, false); $fraudMessage = ''; if ((int)$amountToBePaid !== (int)$paidAmount) { $fraudMessage = '<br/><span style="color:#F00">Cost of product is <strong> NRs. ' . $amountToBePaid . '</strong> but user has paid only <strong> NRs. ' . $paidAmount . '</strong>. Might be the fraud transaction!</span>'; } return $fraudMessage; } }