Here is a step by step how to guide on how to change your website name, this is required if you have a different ingame name to your website name.
Please follow the step below
Go to your profile page, click on your name in the top right and a drop down shall appear, then simply click on your name.
Once on your profile, please select the edit icon next to your name.
Then finally enter your name which should be exactly the same as the name which you will use in-game