Hello mill06012,

I see that the other account has been locked. Unfortunately I can't tell you why.
There are according to history no posts since 2016. Since when is the problem with the login?

I would recommend you to contact the mail address from the message and/or to the one from this thread: Recovering hacked/lost accounts
There are a few ways to find out if you are the original owner of this account. You have to expect some waiting time though.