# Errors

If for any reason the **PKSA** fails to process the challenge request, it can inform the **HAS** with the following message

### challenge\_err

```javascript
{
    cmd: "challenge_err",
    uuid: string,
    error: string,
    pok: string
}
```

{% tabs %}
{% tab title="Properties" %}

* **`uuid`**: the transaction request identifier
* **`error`**: an error message encrypted with the `auth_key`
* **`pok`**: the `uuid` encrypted using the account private key and the HAS server public key (see [Proof of Key](https://docs.hiveauth.com/has-for-wallets-pksa/proof-of-key))
  {% endtab %}
  {% endtabs %}