Also i've found the way to change my name as well. It worked if name is changed from this site https://one.ubuntu.com/ , i don't why but it didn't work for me when i was trying to change from this page directly https://login.ubuntu.com/
Also i've found the way to change my name as well. /one.ubuntu. com/ , i don't why but it didn't work for me when i was trying to change from this page directly https:/ /login. ubuntu. com/
It worked if name is changed from this site https:/