2-Factor Authentication, also known as 2FA, is an extra layer of security that is known as “multi factor authentication” that requires not only a password and username but also something that only that user has on them, i.e. a piece of information only they should know or have immediately to hand – such as a physical token.
Using a username and password together with a piece of information that only the user knows makes it harder for potential intruders to gain access and steal that person’s personal data.
How to Enable it?
You can enable this per contact on each of your users via the contacts section of your dediserve control panel here https://billing.time4vps.eu/clientarea/details/
More about what is Two-Factor Authentication (2FA) and do you need it at - comparitech.net