In order to add a new domain or subdomain on Protectumus for daily or weekly security checks, you first need to create an account. More details regarding the account creation can be found here: https://protectumus.com/kb/details/how-to-create-account.

Once you login to your account, you will see the Current Plan area, on top-left side of the My Account page.

There you can see info such as: License ID, Plan type, Plan expiration date, Number of domains, and you will also see two buttons: Upgrade and Billing if you have the Free license, but if you have a paid license you will also see the Downgrade button.

If you press the Upgrade button, you will be able to select a better plan, and if you click on the Downgrade button, you'll be able to select a cheaper plan.

If you press the Billing button, you will be able to extend your current license by changing the number of domains and the plan availability period.