You can only change your name 3 times within a week, after that you must wait until you can change your name back.
#Cant change names
supple bridge
supple bridge
If thats the case you couldve been name lock, not allowing you to create other names for yourself.
If you changed your name 3 times and it was quick, you will have to wait a week to change it.
sturdy atlas
The name may be invalid, have you treid another name?
desert beacon
You may have changed your name to many times