Devices which uses Username and Password have to speak one of the following Protocols:
Go on Add and enter Name, Password and choose your Validity. After entering all details, click on Create.
To Delete users, select all users which should be deleted in the list, go on Delete and confirm your choice.
To change the users password, disable/re-enable or select a new validity period, simply click on the eye symbol next to the user entry, change all needed entries and save them.