curl --request POST \
  --url http://sandbox.mintlify.com/open/v1/order/complete \
  --header 'Content-Type: application/json' \
  --header 'X-GatePay-Certificate-ClientId: <x-gatepay-certificate-clientid>' \
  --header 'X-GatePay-Nonce: <x-gatepay-nonce>' \
  --header 'X-GatePay-Signature: <x-gatepay-signature>' \
  --header 'X-GatePay-Timestamp: <x-gatepay-timestamp>' \
  --data '
{
  "operationType": "CANCEL"
}
'

{
  "code": "0",
  "message": "",
  "data": null,
  "success": true
}