I got something similar to that, except it doesn’t give me an error screen. My html works, but the editors are perpetually loading and all my non-htmls won’t even run.
Welcome to the community! You didn’t provide a link to your Repl and have many in your profile. Which one? Also, are you running a proxy from that Repl? Proxies are against the Replit ToS and seem to be the problem most of the time.