Board Thread:General Discussion/@comment-100.14.50.30-20200409221158/@comment-34888194-20200410165728

Looks like this user meet the age requirements. According to the help page these are the reasons why you cannot create an account:

"Possible reasons why you can't create an account:
 * Your requested username is already taken.
 * Your age is not valid - you do not meet the minimum age requirement for your region.
 * Someone with your IP address has been globally banned/blocked from Fandom.
 * You are experiencing a loop. Try restarting your computer and clearing all cache/cookies/browser history in the last 24 hours."

You also cannot create a username that seem identical to one of the existing username on Fandom for this simple reason: Preventing impersonation.