You can change your name by clicking the profile icon on the upper left part of the home page. 👇

Then, click the name. 👇

You will need the 'Rename Card', in order to change it. Click Move. 👇

Then under the Dia Store, scroll down to the 'Rename Card', and hit Purchase. 👇

Please note that if you're new, you will need to reach the rank Otherworlder IV in order to unlock it and change the name. 👇