{
  "request": {
    "merchantId": "1234567890",
    "merchantSiteId": "987654",
    "clientRequestId": "REQ-2026-05-24-0003",
    "clientUniqueId": "REFUND-INV-100123",
    "amount": "49.99",
    "currency": "USD",
    "relatedTransactionId": "711000000019876543",
    "authCode": "111111",
    "comment": "Customer requested refund - duplicate charge.",
    "timeStamp": "20260524130200",
    "checksum": "a18bf3c52e0d...redacted...001"
  },
  "response": {
    "transactionId": "711000000019999000",
    "externalTransactionId": "",
    "transactionStatus": "APPROVED",
    "status": "SUCCESS",
    "authCode": "111111",
    "gwErrorCode": 0,
    "gwErrorReason": ""
  }
}