Every registered member must use it’s own email address. That means that for every extra member you want to register, you must use the same sequence method -> Register to the site by filling the registration form, buy subscription, pay subscription (even with the same credit card).

IMPORTANT NOTE :

When you first register under your name, you are logged in, in the site with your personal credentials. You MUST first log out before register another member.

You will see a notification in the registration form like the one in the following image :

Screenshot Signout