problem with message

Hello.
I have the following problem.
When I try to go to the page without doing registration and choose to see one classified, when the classified open up, the page to the right there is a field that writes “Have a question?” and i can send messages to the creator of the classifieds .
I want when i don’t register to the page I can not send messages but to ask me if i want to do first registration to the page.

This can be happen?
Thanks

* i send a photo with the problem
* sorry for my english. is not very good