A page on a client site was working two weeks ago and now

Hi,

A page on a client site was working two weeks ago and now all of a sudden it stopped working three days ago. The url for the page is:

http://blackchamberofcommerce.org/membership-application/

I believe that it is using formidable. We’re running wordpress 3.8. PLease let met know what could be cuasing this.

Corn