You can remove users from a group like so: 

  1. On the ‘Users’ tab, select the Groups tab from the menu (beside Users). 

    1. Locate the user you wish to remove & click the ‘x’ at the end of their row. This removes them from the selected group. 

      If there are many users in the group, you may need to use the search function. 
      Changes are saved automatically. You can add users back in to groups in the future too!