# ERC20 Call Back

The ERC20 Callback is specifically designed for handling ERC20 token transactions, such as USDT. Notifications are sent only when the address times out or when a transaction reaches 12 confirmations. If the received USDT amount differs from the required amount, it will be recalculated. The address will time out after 1 hour.

**Transaction Found with 12 Confirmations**

```json
{
    "statusCode": 200,
    "merchant_id": "a56e0-0a10c-73015-9f330",
    "hash": "o3OsLGIMX3KCRGO4plWNhBJqRAiLDU2/L5i+ymIlcliBVWJ/ca6OSmdTb7UAylXQgfpjXZT5ZUC6faYS2aNaQQ==",
    "data": {
        "id": "123123123123",
        "symbol": "USDT",
        "address": "0x0E595b185E323Fa5019E8D73B2F7A3D0f089b582",
        "block": 7677026,
        "txid": "0x73cedead30e3949d0867986f7049923417dd42ca32872aaece85c41703927773",
        "confirmation": 12,
        "balance": 124.6261,
        "usd_balance": 125,
        "timestamp": 1586350781,
        "risk_level": 1
    }
}
```

**Response Parameters**

<table><thead><tr><th width="173">Parameter Name</th><th width="140.33333333333331">Type</th><th>Explanation</th></tr></thead><tbody><tr><td>id</td><td>string</td><td>Order number</td></tr><tr><td>symbol</td><td>string</td><td>Currency type (e.g., 'USDT')</td></tr><tr><td>address</td><td>string</td><td>Address</td></tr><tr><td>block</td><td>string</td><td>Block number</td></tr><tr><td>txid</td><td>string</td><td>Blockchain transaction identifier</td></tr><tr><td>confirmation</td><td>number</td><td>Number of confirmations</td></tr><tr><td>balance</td><td>decimal</td><td>Amount received</td></tr><tr><td>usd_balance</td><td>decimal</td><td>Amount in USD</td></tr><tr><td>timestamp</td><td>number</td><td>Timestamp</td></tr><tr><td>risk_level</td><td>number</td><td>0, pending 1 low, 2 high, 3 medium, 4 severe</td></tr></tbody></table>

**Address timeout**

```json
 {
    "statusCode": 10011,
    "merchant_id": "a56e0-0a10c-73015-9f330",
    "hash": "BxmwfJDRPI8QX5a1EvWU5+iyfRxKsyo9nJL+ZeCpQPHeyRLvlAq9lRGrDLslIDIK5iLh0jXVXndiHZyeL4R28A==",
    "data": {
        "address": "0xC723d774363394de659EaA70a1DE7d40A50b90C4",
        "msg": "Address timeout",
        "timestamp": 1586350652
    }
}
```