> For the complete documentation index, see [llms.txt](https://docs.neox.vn/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.neox.vn/docs/payment-gateway/transaction-management/cancel.md).

# Cancel

### Structure of Cancel Request

<mark style="color:blue;"><https://neopay-domain?\\[key1=value]&\\[key2=value]&>...</mark> (below table is the description of key and value, no ordering required)

**Method**: POST

### Table of Parameter

<table><thead><tr><th>Parameter</th><th width="117">Data type</th><th width="101">Required</th><th>Description</th></tr></thead><tbody><tr><td>neo_Command</td><td>String</td><td>Y</td><td>“CANCEL” as default</td></tr><tr><td>neo_MerchantCode</td><td>String</td><td>Y</td><td>The merchant code is provided by NeoX</td></tr><tr><td>neo_MerchantTxnID</td><td>String</td><td>Y</td><td>Unique - The merchant transaction ID is provided by merchant</td></tr><tr><td>neo_Version</td><td>String</td><td>Y</td><td>Version of API, "1" as default</td></tr><tr><td>neo_SecureHash</td><td>String</td><td>Y</td><td>Use <strong>SHA256</strong> to hash the above parameters (sort the key by Alphabet order) + Secret Key (is provided by NeoX after actual integrating)</td></tr></tbody></table>

### Table of Data Response

<table><thead><tr><th width="200">Parameter</th><th width="117">Data type</th><th>Description</th></tr></thead><tbody><tr><td>neo_ResponseCode</td><td>Number</td><td>Result of transaction:<br>0: transaction success<br>!= 0: transaction failed, refer to <a href="/pages/kU24dUIxUPVgYJPLKotj#table-of-error-code">table of error code</a></td></tr><tr><td>neo_ResponseMsg</td><td>String</td><td>Refer to <a href="/pages/kU24dUIxUPVgYJPLKotj">table of error code</a></td></tr></tbody></table>

*Note: Should call this API 5 mins after payment made.*


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