I’m not sure myself either. In my case I simply didn’t have access to my GitHub email address to confirm login and choose to use an email I did have access to.
Thanks for making me aware of this. Not sure what the default setting is or if the admins of the forum have customized it but I’ll just wait and try to sign-up again once purged.
Note on the above, I’ve reduced the number of steps to reproduce from 11 to 8.