> For the complete documentation index, see [llms.txt](https://prepaidify.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prepaidify.gitbook.io/docs/physical-card/api-integration/bank-card-replacement.md).

# Bank Card Replacement

### POST Bank Card Replacement

POST /api/mastercard/changeCard.html

Replace a bank card. Note: After a successful card replacement, the old card will be frozen, and the new card will be automatically activated using the cardholder information from the old card. The balance from the old card will be transferred to the new card within 24 hours. During this period, please ensure the security of the card to prevent any user losses.

> Request Body

```
```

```json
{
  "cardId": "card123",
  "cardNo": "**** **** **** 1234",
  "cvv": "123",
  "oldCardId": "old_card123",
  "oldCardNo": "**** **** **** 5678",
  "randomStr": "abcdef1234567890"
}
```

#### Request Parameters

| Name      | Type   | Required | Base64 Encoded | Description                                              |
| --------- | ------ | -------- | -------------- | -------------------------------------------------------- |
| cardId    | string | false    | none           | cardId or cardNo must be filled in at least              |
| cardNo    | string | false    | none           | cardId or cardNo must be filled in at least              |
| cvv       | string | false    | none           | CVV will be validated if provided                        |
| oldCardId | string | true     | none           | Either oldCardId or oldCardNo must be filled in at least |
| oldCardNo | string | true     | none           | Either oldCardId or oldCardNo must be filled in at least |
| randomStr | string | true     | none           | 32-digit random string                                   |

> Example Response
>
> 200 Response

```
```


---

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