Gitlab pages not serving the correct file under custom domain

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Problem to solve

Hello,
I have a repository with my personal website. I want to set up the website to serve an HTML file I put to my repository: https://gitlab.com/samokosik/my-website
I have set up everything according to the instructions. However, I get 2 errors:

  1. Something went wrong while obtaining the Let’s Encrypt certificate for samokosik.com. To retry visit your domain details.
  2. the server is serving me a completely different site. Something which says pixie proxy (check out samokosik.com) instead of the HTML I provided.

Steps to reproduce

I have tried to verify that my html file is correct and it indeed is. Gitlab says something regarding to Let’s Encrypt certificate for samokosik.com. is broken. But that has nothing to do with the fact that it pulls HTML from somewhere else.

Configuration

here is the domain setup:

Versions

Please add an x whether options apply, and add the version information.

  • Self-managed
  • [ x] GitLab.com SaaS
  • Dedicated