GitLab Pages suddenly redirecting to sign in - visibility untouched and set to 'Everyone'

We are using GitLab pages with a custom domain. Suddenly today, when accessing GitLab pages we get redirected to a GitLab sign in page. When signed in, we get taken to a 404 page.

  • This was working fine previously and there have been no commits to the project since before it went offline.
  • We’ve checked the ‘visibility’ setting in the project, it’s still set to ‘Everyone’. I’ve tried flipping and flipping back, just in case.
  • The artefacts from the build are the same as before - and I’m just trying to access a static file I can see artefact in the deployment - and as mentioned, there have been no new commits anyway.

What else could we be missing? Thanks