As a normal member here we can't change our name chosen but if you are staff here you can do that.
As far as I know, a staff member here who change their name is our mode in local. Rickbig to
Mr. Big I think only Global Moderator can do that.
Hi, how can I change the name of my account?
So what your purpose in changing username?
And what happens when people change their name here to try hide their 'crimes' or wrongdoing (either here or elsewhere)?
Read this.