When trying to access my repository, I get,
"Whoops, something went wrong on our end.
Try refreshing the page, or going back and attempting the action again.
Please contact your GitLab administrator if this problem persists."
I had no idea where to post this so here this is. 
I’ve got the exact same issue on one of my Repositories too.
Fetching the content over git works just fine.
Same issue here. I can open up all but 2 of my repos, one public and one private, both giving the same 500 error on the landing page. I also get the same 500 error on the public repo if I pull it up on a private browsing session not logged in. I did notice that I can still access the repo sub-pages (like /username/reponame/edit) if I load them directly.
FWIW I was also affected by 2021-09-03: Users getting 422 errors when trying to log in (#5473) · Issues · GitLab.com / GitLab Infrastructure Team / production · GitLab so maybe they’re somehow related
see longer thread here about the issue Consistent 500 error from gitlab.com for one repository - now tracked at Project homepage not accessible (500 internal server error) (#340037) · Issues · GitLab.org / GitLab · GitLab
Now, all my projects are available again! 
