> ## Documentation Index > Fetch the complete documentation index at: https://docs.commercepay.asia/llms.txt > Use this file to discover all available pages before exploring further. # Refund Payment > **The payment gateway requests a refund payment** Initiate a full or partial refund for a successful payment transaction. See [Refund Integration](/docs/refund-integration) for full vs. partial refund behavior and bank support. The response's `refundStatus` reflects the outcome directly — if it comes back as `ProcessingRefund`, use [Query Refund Payment](/api-reference/query-refund-payment) to check when it completes. ## Errors In addition to standard signature errors, this endpoint can return: | Code | Name | Meaning | | ---- | ------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | 2010 | `TransactionNotFound` | `transactionNumber` does not match a transaction, or the transaction is not in `Success` status. | | 2042 | `FailedToRequestRefund` | Generic refund failure. The message names the specific cause, e.g. a refund is already in progress for this transaction, the requested amount exceeds what's still available to refund, the channel doesn't support partial refunds, or the provider is unavailable for this channel. | | 2044 | `MissingRequireField` | `reason` was not supplied. | | 2094 | `InvalidTenantProfile` | Tenant could not be resolved (no session tenant and no `tenantId` in the request body). | | 2124 | `RequestRefundTimeOut` | The provider's refund API timed out while processing the request. | | 2130 | `ChannelNotSupportRefund` | The original transaction's channel is configured to not support refunds. | | 2160 | `InvalidPaymentGatewaySetting` | The channel's provider settings are missing or misconfigured for this tenant. | > A refund amount of `0` (or negative) is also rejected via `FailedToRequestRefund` (2042), with the message "Refund amount cannot be 0". ## OpenAPI ````yaml /openapi.json post /api/services/app/PaymentGateway/RefundPayment openapi: 3.0.1 info: title: CommercePay API version: v1 description: > --- **Credentials Accounts** Every account is provided with separate keys for testing and for running live transactions. Once the merchant application has been approved, developers can begin the process of integrating the CommercePay API. The following details will be provided to get started with the integration. Get Started contact: {} servers: - description: Staging url: https://staging-payments.commerce.asia - url: https://payments.commerce.asia description: Production security: [] paths: /api/services/app/PaymentGateway/RefundPayment: post: tags: - PaymentGateway summary: Refund Payment description: >- **The payment gateway requests a refund payment** Initiate a full or partial refund for a successful payment transaction. See [Refund Integration](/docs/refund-integration) for full vs. partial refund behavior and bank support. The response's `refundStatus` reflects the outcome directly — if it comes back as `ProcessingRefund`, use [Query Refund Payment](/api-reference/query-refund-payment) to check when it completes. operationId: ApiServicesAppPaymentgatewayRefundpaymentPost parameters: - $ref: '#/components/parameters/AbpTenantId' - $ref: '#/components/parameters/Authorization' - $ref: '#/components/parameters/CapSignature' requestBody: content: application/json-patch+json: schema: $ref: '#/components/schemas/RefundPaymentInputDto' application/json: schema: $ref: '#/components/schemas/RefundPaymentInputDto' text/json: schema: $ref: '#/components/schemas/RefundPaymentInputDto' application/*+json: schema: $ref: '#/components/schemas/RefundPaymentInputDto' responses: '200': description: Success content: application/json: schema: $ref: '#/components/schemas/RequestRefundOutputDto' examples: Example 1: value: tenantId: 0 transactionNumber: string refundTransactionNumber: string referenceCode: string amount: 0 currencyCode: string refundStatus: 11 responseMessage: string paymentSessionNumber: string refundPaymentList: transactionNumber: string amount: 0 currencyCode: string refundReason: string refundStatus: 11 text/json: schema: $ref: '#/components/schemas/RequestRefundOutputDto' text/plain: schema: $ref: '#/components/schemas/RequestRefundOutputDto' '400': description: Bad Request content: application/json: schema: $ref: '#/components/schemas/ErrorOutputDto' examples: TransactionNotFound: value: code: 2010 message: >- transactionNumber does not match a transaction, or the transaction is not in Success status. FailedToRequestRefund: value: code: 2042 message: Refund amount cannot be 0 components: parameters: AbpTenantId: schema: type: string in: header name: Abp-TenantId required: true description: Your unique Merchant ID assigned by CommercePay. Authorization: schema: type: string in: header name: Authorization required: true description: Your API credentials used for authentication (typically a Bearer token). CapSignature: schema: type: string in: header name: cap-signature required: true description: >- A unique security hash used to verify the integrity of the request body. See [Generate Signature](/docs/generate-signature) for how to generate this. schemas: RefundPaymentInputDto: type: object additionalProperties: false required: - transactionNumber - reason - timestamp properties: transactionNumber: type: string description: Unique CAP Transaction Number maxLength: 24 nullable: true reason: type: string description: A description for refund. example: Purchase wrong item nullable: true amount: type: integer description: "Please take note: The Amount parameter only accepts integer units. For example, 1000 is equivalent to 10.00 for the backend.Show all...\r\n\r\n\r\nExample: 100\r\n\r\n[Please pass the required amount if issuing a partial refund; ignore this attribute if issuing a full refund.]" format: int32 nullable: true timestamp: type: integer format: int64 description: new Date().getTime() example: 1621851652617 RequestRefundOutputDto: type: object additionalProperties: false x-internal: false properties: tenantId: type: integer format: int64 description: Merchant ID. transactionNumber: type: string description: >- Unique CAP Transaction Number of the original payment being refunded. maxLength: 24 nullable: true refundTransactionNumber: type: string description: >- Unique CAP Transaction Number for the refund transaction itself, distinct from the original payment's transactionNumber. nullable: true referenceCode: type: string description: Merchant Reference Code nullable: true amount: type: number format: double description: "Please take note: The Amount parameter only accepts integer units. For example, 1000 is equivalent to 10.00 for the backend.\r\n\r\nInvalid Format: 1,000.00" example: 100 currencyCode: type: string description: Currency code with a 3-letter ISO 4217 standard code example: MYR maxLength: 3 nullable: true refundStatus: $ref: '#/components/schemas/RefundStatus' responseMessage: type: string description: Human-readable status message for the refund request. nullable: true paymentSessionNumber: type: string description: Unique CAP Session Number maxLength: 24 nullable: true refundPaymentList: $ref: '#/components/schemas/RefundPaymentListDto' x-examples: Example 1: tenantId: 0 transactionNumber: string paymentSessionNumber: string refundTransactionNumber: string referenceCode: string amount: 0 currencyCode: string refundStatus: 0 refundPaymentList: - transactionNumber: string amount: 0 currencyCode: string refundReason: string refundStatus: 0 responseMessage: string ErrorOutputDto: type: object additionalProperties: false properties: code: type: integer description: See the Errors table above. message: type: string nullable: true RefundStatus: enum: - 11 - 12 - 13 - 16 - 17 - 18 type: integer format: int32 x-enumNames: - Refunded - ProcessingRefund - FailedRefund - RefundWithCharges - RefundReverse - Voided description: >- Status of the refund itself (not the original payment). | Value | Name | Meaning | | ----- | ---- | ------- | | 11 | `Refunded` | Refund completed successfully. | | 12 | `ProcessingRefund` | Refund request accepted, being processed by the provider. | | 13 | `FailedRefund` | Refund attempt failed. | | 16 | `RefundWithCharges` | Refund completed, but provider/processing charges were deducted from the refunded amount. | | 17 | `RefundReverse` | A previously completed refund was reversed by the provider. | | 18 | `Voided` | The original transaction was voided instead of refunded, e.g. same-day cancellation. | RefundPaymentListDto: title: RefundPaymentListDto type: object properties: transactionNumber: type: string description: Unique CAP Transaction Number maxLength: 24 nullable: true amount: type: number format: double description: Refund Amount. example: 100 currencyCode: type: string description: Currency code with a 3-letter ISO 4217 standard code example: MYR maxLength: 3 nullable: true refundReason: type: string description: A description for refund. nullable: true refundStatus: $ref: '#/components/schemas/RefundStatus' ````