I’m having the same kind of issue: I can't login to my account because my email service provider doesn't work anymore
I am the owner of this profile: https://wiki.developer.mozilla.org/en-US/profiles/milc
It is associated with an @vmail.me address, this provider has closed and I am lock-out of my mozilla account.
I logged-in with my Github account to publish a contrib on MDN. So, I have now 2 accounts.
Is there a way to regain access to my old account? Maybe to “merge” them? Or is it lost forever?
Thanks in advance!