Meanwhile, my phone is a potato that is slow to actually solve the proof of work challenges.
I can access it ok on Firefox on Android FWIW.
Not sure how that helps the parent commenter.
It might help narrow in on the specific issue in case they are using some other browser
You can take it as another data point. Here's another one: it works for me on Firefox/Android too. It might imply that the issue is probably not with that specific combination but something else. Maybe disabled cookies? Just an idea.