I hit exch.cx on Tor Browser, get redirected to - hszyoqwrcp7cxlxnqmovp6vjvmnwj33g4wviuxqzq47emieaxjaperyd.onion - and the connection times out. Is there a problem?
For me it took a long time to load but there was no other issue.
You most likely visited the "http" version of the website which still loads normally, the "Https" version is not available at the moment for some reason. Perhaps it's temporary. I wouldn't use the "Http" version for any transaction for now until it's rectified.