I'm not at all sure what you want me to take a look at.
On your site I dont see a way to register and/or login.
I just tried creating another add, I got the email, and it linked to the attivazione_annuncio.php but i dont see a username or password to use, and I don't see a link to login.
I'm not at all sure what steps I am supposed to be taking to reproduce the problem you are reporting, it is not clear form you description of the problem what to do, or what the problem is.