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This entry covers the API changes released on September 29, 2026.

## New unified response codes

We've added new decline and error codes to the [Pay In unified response codes reference](/guides/pay-in-unified-response-codes-reference), including a new section for 3-D Secure (3DS) authentication declines. These codes apply to Pay In transactions made with v2 of the API.

### 3-D Secure decline codes

The `D2001`-`D2049` range is now reserved for 3DS-related declines. Codes `D2001` through `D2023` cover issuer declines and challenges, cardholder authentication failures, duplicate authentication values, and 3DS processing errors. All return HTTP status `402`.

### Other new response codes

| Code    | HTTP Status Code | Reason                                          |
| ------- | ---------------- | ----------------------------------------------- |
| `D0328` | 402              | Invalid amount or currency                      |
| `D0482` | 402              | Missing or incorrect wallet type                |
| `D0533` | 402              | Invalid MAC received                            |
| `E5050` | 400              | Surcharge not allowed for card type             |
| `E5051` | 400              | Surcharge not allowed for non-US issued card    |
| `E5052` | 400              | Surcharge not allowed at this paypoint location |
| `E5053` | 400              | Surcharge not allowed for payor's location      |
| `E5054` | 400              | Paypoint not registered for surcharging         |
| `E5055` | 400              | Surcharge not allowed with service fee          |
| `E5056` | 400              | Calculated surcharge amount mismatch            |
| `E7069` | 400              | Device busy                                     |
| `E9070` | 400              | Device timeout                                  |
| `E9075` | 400              | Transaction canceled by user                    |

See the [Pay In unified response codes reference](/guides/pay-in-unified-response-codes-reference) for the full description and resolution text for every code.