using Gr4vy;
using Gr4vy.Models.Components;

var sdk = new Gr4vySDK(
    id: "example",
    server: SDKConfig.Server.Sandbox,
    bearerAuthSource: Auth.WithToken(privateKey),
    merchantAccountId: "default"
);

var res = await sdk.Transactions.Refunds.CreateAsync(
    transactionId: "7099948d-7286-47e4-aad8-b68f7eb44591",
    transactionRefundCreate: new TransactionRefundCreate() {}
);

// handle response

{
  "type": "refund",
  "id": "6a1d4e46-14ed-4fe1-a45f-eff4e025d211",
  "transaction_id": "7099948d-7286-47e4-aad8-b68f7eb44591",
  "payment_service_refund_id": "refund_xYqd43gySMtori",
  "status": "succeeded",
  "currency": "EUR",
  "amount": 1299,
  "reason": "Refund due to user request.",
  "target_type": "payment-method",
  "target_id": "07e70d14-a0c0-4ff5-bd4a-509959af0e4d",
  "reconciliation_id": "7jZXl4gBUNl0CnaLEnfXbt",
  "external_identifier": "refund-12345",
  "transaction_reconciliation_id": "aLEnfXbt7jZXl4gBUNl0Cn",
  "transaction_external_identifier": "transaction-12345",
  "created_at": "2013-07-16T19:23:00.000+00:00",
  "updated_at": "2013-07-16T19:23:00.000+00:00",
  "creator": {
    "email_address": "jhon.doe@gr4vy.com",
    "id": "07e70d14-a0c0-4ff5-bd4a-509959af0e4d",
    "name": "Jhon Doe"
  }
}