Click on Admin icon at the sidebar on the left. By default sub-menu Departments belonging to Groups  is highlighted

 

Click on Users & Roles from the top menu. All the users created are listed here.



Ensure that there are at-least two users in an Account. Select an User from the list. 


For the highlighted user , click on delete icon at the right


Click on the button Delete User. 


If the deletion of User was successful a green banner appears at the bottom right.