> For the complete documentation index, see [llms.txt](https://chainge-finance.gitbook.io/chainge-finance/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chainge-finance.gitbook.io/chainge-finance/get-started/chainge-2.0-api-documentation/submit-ticket.md).

# Submit Ticket

### Header

<table><thead><tr><th width="189">Fields</th><th>Description</th></tr></thead><tbody><tr><td>Evmaddress</td><td>The current address of the user's connected wallet.</td></tr><tr><td>Signature</td><td>The user's signature of the post body</td></tr></tbody></table>

### Body

<table><thead><tr><th width="191">Fields</th><th>Description</th></tr></thead><tbody><tr><td>hash</td><td>Problematic transaction hash</td></tr><tr><td>chain</td><td>From chain nickName</td></tr></tbody></table>

***Signature***:

To obtain a correct interface signature, we need to follow these 5 steps:

1. Construct the body parameter object correctly according to the requirements.
2. Concatenate the parameters of the complete body parameter object, sorted alphabetically, using '&' as a separator. For example:  *`chan=FSN&hash=0x4190dc4627cb4e97292...`*
3. Prefix the string generated in **`step 2`** with **`EvmAddress=...&{result of step 2}`**, for example: *`EvmAddress=0x42a6685ef29886Cbcb595Aa903f00dea0d1787d8&chan=FSN&hash=0x4190dc4627...`*
4. Apply **`keccak256`** hashing to the result of **`step 3`**.
5. Sign the result of **`step 4`** with the wallet.

***get Signature*** examples：

```javascript
sortParams = (params, evmAddress) => {
    let keys = Object.keys(params)
    if(!keys.length) return undefined
    keys = keys.sort();
    const keyValList = []
    for (const key of keys) {
        const val = params[key];
        if(val) {
            keyValList.push(`${key}=${val}`)
        }
    }
    const data = keyValList.join('&')
    const raw = `EvmAddress=${evmAddress}&${data}`
    return raw
}

// step 1
const bodyParams = {
    chain: "FSN",
    hash: "0x4190dc4627cb4e97292b6b718d718d3c3af93f14477346efc181ff549f69f794"
}

// step 2 & setp3
let raw = sortParams(bodyParams, '0x42a6685ef29886Cbcb595Aa903f00dea0d1787d8') as string;
console.log(raw) // EvmAddress=0x42a6685ef29886Cbcb595Aa903f00dea0d1787d8&chan=FSN&hash=0x4190dc4627cb4e97292b6b718d718d3c3af93f14477346efc181ff549f69f794

// step4
raw = keccak256(toHex(raw));
console.log(raw) // 0x86a444bc2c6104a3aadcf82c00dc6328fea2bd3472298369dedcbdb592ad257d

// step5 Calling wallet message signing
// Calculates an Ethereum-specific signature in EIP-191 format: keccak256("\x19Ethereum Signed Message:\n" + len(message) + message)).
// Note: The signature should not include the prefix '0x'.
let signature = wallet.signMessage(raw)
```