Your class information can be modified including the name of the class, by clicking on the menu of the class.
The main menu is reachable by clicking on the bottom pointing arrow, at the upper right of your class on the welcome page. Select “modify the class” in order to change the information concerning your class (picture, name, level, settings, etc).
Specificity : It is not possible to change the key to your class. If it does not suit you, you will have to remove your class and create a new one with the key you would like to use.