# hostname_is_public_suffix

That hostname is a public suffix, so nobody can prove control of it.

## What it means

The hostname is on the Public Suffix List, like `co.uk` or `github.io`: many unrelated people register names under it, so no single owner can prove control.

## Why it happens

- The customer typed only the suffix of their domain.
- A shared hosting suffix was used (`*.github.io`, `*.vercel.app`) where each customer owns only their own label.

## What to do

1. Add a hostname under the suffix, like `careers.example.co.uk`.
2. For shared hosting suffixes, add the customer's full name (`acme.github.io`).

- [Open the dashboard](/app/domains)
- [All limits](/docs/limits-and-pricing)

## In the API

```
HTTP 422

{
  "error": {
    "code": "hostname_is_public_suffix",
    "message": "That hostname is a public suffix, so nobody can prove control of it.",
    "fix": "Add a hostname under it, like careers.example.co.uk.",
    "docs": "https://apexly.dev/docs/errors/hostname_is_public_suffix"
  }
}
```