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usernames

If I change my username to an username whose account is banned, will I be able to take the username or do I have to contact support?
It depends on the reason the account was banned and how long ago it was active. Also, some abuse closures may not allow reuse of the name.

https://www.chess.com/member/bIitz like if i try to take this name by changing my name in the settings, will it work? or would it say taken?

Why do you want to do that in the first place gang thats an oddly specific question
im asking for someone else im not changing it to that

https://www.chess.com/member/bIitz like if i try to take this name by changing my name in the settings, will it work? or would it say taken?
You can't change a username to one that already exists. Staff have to change the original to free it up for use.
If I change my username to an username whose account is banned, will I be able to take the username or do I have to contact support?