Hi. I set up everything as the documentation follows. I see that the invitation link get sent only if the user is registered right?

When i click on the link, if i’m logged out, the page is the registration step. Of course if i register with the email into which i got the invitation the error message is “User email already registered” . If i am logged in and click the invitation link i get sent to the security page and than i can’t do anything. So how does it works in this stage? i can’t understand.