Go to Settings
Select the profile to edit
In the opened profile, select the Deactivate User button in the upper right hand corner.
The profile will update immediately to reflected deactivated. The users will no longer have access within the system. If they are logged into the mobile app at the time, the app will no longer work properly, forcing the user to log out. Once logged out, they will no longer be able to login.
To reactivate the profile, select the green Activate button.