Troubleshooting
Four problems, and three of them are the browser or the network rather than the directory. Each says how to tell which you have.
The repository list is empty
Usually GitHub's anonymous rate limit, which is about sixty requests an hour per address. The page will say so and show the last copy it had if there is one.
Waiting an hour is the fix. There is no button to speed it up and no way to raise it, because the limit belongs to GitHub and applies to every unauthenticated site on the internet equally.
An empty list with no message about a limit is a different problem: the browser is blocking the request. Check api.github.com in your network tools.
Every site reads as no answer
That is your connection, not the sites. The check is a real request from where you are, and three things commonly produce a wall of failures: a captive portal, an extension that blocks cross-origin requests, or a network that cannot reach Cloudflare Pages.
Confirm it by opening one of the three addresses directly in a new tab. If that works and the check does not, the problem is between the page and the address rather than the address itself.
One site reads as answering and the others do not
Worth believing, and the one case where the reading is likely true. There is a six-second timeout and no retries, so a single slow response reads as a failure.
Use the history column rather than the current reading. Several failures across many checks means something; one is a hiccup. The history is kept per browser for seven days, which is long enough to tell those apart.
The numbers look old
Compare the age shown against the data. Fifteen minutes is the cache lifetime for repositories and seven days for check history, and both are stated on the page rather than left for you to guess.
A repository count that has not moved in months is not a bug. It means nothing public has been pushed in that time.