I need to change my username, from jguo52 to jguo5258 but “jguo5258” is already taken by someone who is impersonating me. I contacted github support but it has been over a week with no response.
I’m sorry this has happened to you. We’re not able to handle impersonation cases on the forums.
I did find a ticket from you in August, where support did reply.
It may be worth checking your spam folders to see if that reply got missed somehow.