# Errors

```json
{
  "code": 422,
  "status": "failed",
  "message": "face1 is required"
}
```

| HTTP status | Meaning | Common messages |
| --- | --- | --- |
| `400` | Comparison, billing, or usage processing timed out. | `access timeout` |
| `401` | Credentials or merchant key could not be authenticated. | `invalid authorization`, `invalid merchant key`, `authentication failed` |
| `403` | The integration cannot use this service or has insufficient balance. | `forbidden`, `insufficient balance` |
| `422` | The JSON body, transaction ID, or an image is invalid. | See validation messages below. |
| `503` | The service is under maintenance. | `service is currently under maintenance` |

Validation can return:

- `invalid payload`
- `empty transaction_id`
- `transaction_id length must be between 1 and 255 characters`
- `invalid transaction_id`
- `face1 is required`, `face1 invalid`, or `face1 invalid type`
- `face2 is required`, `face2 invalid`, or `face2 invalid type`
- `invalid size selfie` when either decoded image exceeds the configured limit