It's working fine for me, seems like it's just your browser issue. Clear cache or do hard refresh via CTRL+F5.
Ps: That's cloudflare error page's source code.
I did clear that already, but when i put Identifier and click enter, i got that error on full page. And after few seconds it vanished and again the same issue.
So what is the Issue
No im not getting any error, i can login to this site with out any problem. I think you are putting some thing wrong like password, Alice etc
No im entering the correct password and Identifier