Whilst we have seen some that can’t connect to the account from the UI - I also find I can’t connect either - I was thinking that this could be a back end server issue.
That however doesn’t appear to be the case - firstly I had been browsing in the forums (and showed logged in - I was also able to connect to my.avast.com using my browser.
Note I didn’t have to log in as I was recognised, even so I believe that it indicates that the server would be working correctly.