They have a Help Center link....
I’ve never used it, but maybe you can find out what’s going on there.
Thank you. That’s the page that says “Unauthorized! Sorry, you don’t have access to this page.” with a hotlink that says “Go back home.” When I click it it just refreshes that page. No other Twitter link works for me either. I can get that page or I can get a sign in page and neither one works.