Thanks for the persistence :)

The game is hosted on Cloudflare so it should be highly available across the world. The only thing that comes to mind is the stale DNS cache, the delvers.io domain was registered a few weeks ago and theoretically this record might have not been propagated.

Could you please try flushing the DNS cache by following this or any other guide:

https://grok.lsu.edu/article.aspx?articleid=19328