IIRC, accounts used to be locked automatically if you used this question to restore your account... It was a security feature that was added after the big database hack that happened around 2015 (IIRC, my memory is quite rusty). After the database was leaked, everybody who bought a copy could use the secret question to try to steal any account, so the admin decided to disable the feature and lock any account that attempted to use the secret question so hackers could not steal it...
OP claims he never tried to restore his account with the secret question. He logged into his account back in 2018. I wonder why he didn't see the
account locked notification back then?! The database leak happened in 2015, he should have seen the same notification in 2018 as well right?
@OP Is this the first time you try to recover your account or did you try it sometimes in 2018 as well?
I noticed that the current account the OP is accessing is also inactive for quite some time.
The OP was able to log into the newbie account and was unable to log into the legend account. The second account was created a long time ago. It is possible that even then some questions arose for which there was a need for a second account. After all, the nickname has remained the same.