Note: As an app manager, you can delete only those users that you have invited yourself.
To delete a user as administrator or app manager, follow these steps:
Open the app Administration.
Open the menu item User Management > Users.
Select the corresponding user from the list.
Confirm with Yes that you really want to delete this user.
Note: If the user is still involved in actions in another app, the user cannot be deleted. The administrator or app manager is informed in a message which app which app is affected and can then complete the actions or assign them to another user.
Find more information here: