Troubleshoot lightbox JavaScript on my unbounce landing page

I'm using a lightbox contact form on an unbounce landing page. When I submit the form on any computer, the form submits and behaves as expected: the form disappears and a success message is displayed. When I submit the form on a mobile device, the form data is cleared out, and the success message is loaded in a modal window behind the form (so when you click to close the empty form, you see the success message). I believe this is an issue with the lightbox (fancybox) script I am using, and I need help troubleshooting/updating the script so the form continues to submit as needed on desktop, and on mobile, the form modal closes on submit to show the success message.