hostname_is_public_suffix

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).