> For the complete documentation index, see [llms.txt](https://developers.mtpelerin.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.mtpelerin.com/integration-guides/parameters-and-customization/automating-the-end-user-address-validation/troubleshooting.md).

# Troubleshooting

Most common causes of an invalid address validation

{% hint style="warning" %}
Make sure to have properly URL encoded the parameters.
{% endhint %}

| Symptom                                         | Cause to check                                                                                      |
| ----------------------------------------------- | --------------------------------------------------------------------------------------------------- |
| The signature is refused on every chain         | The signed message must be `MtPelerin-{code}` with the code you passed in the URL.                  |
| The signature is refused, EVM or Bitcoin        | `+`, `/` and `=` were not URL encoded as `%2B`, `%2F` and `%3D`.                                    |
| The signature is refused, Tezos                 | The block does not have exactly 6 lines, or the newlines were not encoded as `%0A`.                 |
| The signature is refused, Tezos                 | The public key on line 4 does not correspond to `addr`.                                             |
| The signature is refused, smart contract wallet | The `chain` parameter is missing or points to the wrong network.                                    |
| The address is never offered to the user        | Wrong `net`, or the address family does not match the network.                                      |
| The validation is rejected                      | `code` is not exactly 4 digits, or the address is already registered on another Mt Pelerin account. |