You can easily add, edit or archive all of your users through Settings. Here is a step-by-step guide on how to edit any user.
Click on Settings in your left side menu. It is highlighted in magenta below.
Click on Branch Settings to find the list of current branches:
Click on the name of the user you wish to edit's branch:
Find the user and click on the edit button next to their name
Update the information and click save.