I can't log into my Stack Overflow account using Google Mail. When I do I get this error message:
When I log in using another Stack Exchange account and check the list of communities that I'm on, Stack Overflow doesn't show up:
When I visit Stack Overflow (still logged in via the other StackExchange account) I get the Join this community button as if I'm not:
Trying to join also fails.
Visiting my Stack Overflow user page shows that I'm currently on only one StackExchange community, the others are missing. It's as if my Stack Overflow account is detached from my other Stack Exchange accounts and I can't access it anymore.
How to fix this? How can I log into my Stack Overflow account? How can join those Stack Exchange accounts back?