Easy Fancy box stops working in gravity form multiple step

Hi We are facing a problem when using multiple step form with easy fancybox. The problem is, we have a link in the first step of a multiple step form, that when clicked open a lightbox with some information on it. The problem occurs when we try to go to the next form step and forget to fill any required field. For our surprise when we try to open the lightbox again it doesn't work anymore.

The same occurs when we have others links (opening lightbox) across the steps of the form. In the first step everything works fine but when we step ahead the lightbox stops opening.

Have you ever faced a problem like that?

That's the page that contains the form i've described.

The required field is the one with the label: "Li e concordo com os termos do contrato"

http://novohosting.netpoint.com.br/hospedagem-aplicar-teste/

The link: "termos do contrato"

1) try to submit the main form "Plano Básico" without check the item "Li e concordo com os termos do contrato" (Which opens the lightbox)

2) the item "Li e concordo com os termos do contrato" is a required field, and you will not be able to go to step 2, then try to open the lightbox, you will notice that it is not possible to open it anymore.