Your WordPress username is one of the few options that you can’t edit, within your user profile.
Why would you need to change your WordPress username?
There are a few reasons why you might want to change your WordPress username:
You don't like your username.
Maybe you messed up when creating your username, or perhaps you hired someone to design your website, and the username they created for you, wasn't your cup of tea. That's okay. This article will help you fix that.
Your username isn't secure.
If you're using a username like 'admin', it's one of the most hacked. Most bots that are programmed to hack and do brute force attacks or DDoS attacks, look for that particular username. Brute force attacks are when many bots attempt to log into your site at one time, and either gain entry, or in some cases get the site to shut down.
In securing your WordPress site, make sure not to use 'admin' as your username. If you do have it set to that, then you definitely should be changing your WordPress username. Once a hacker figures out the username, they only need to figure out the password.
How to Change a WordPress Username
There are two methods you could try when you want to change a WordPress username:
Using a plugin
Using phpmyadmin
While it is an option, It’s not necessary to re-create a new user and delete your old one, when you can change them with a plugin or via the database. You can certainly try this, but it’s safer, so you don’t lose the content you have already created, and accidentally deleted your old username.
Using a plugin