I have tried searching the database for a similar issue, but was unsuccessful in finding anything remotely close. I just noticed that the sub menu items on two pages on a site I am creating that use php or are php have stopped working. Nothing was changed on the menu items as they are library items that have not been detached from the original. 

Instead of attaching the entire code for both pages (as they are quite long), I figured I would first provide a link to the testing server that the two pages in question are hosted on: (1) <http://2142.sandbox.i3dthemes.net/apply_now.php> and (2) <http://2142.sandbox.i3dthemes.net/contact_us.htm>. 

If you think you know what is happening here, I would be very curious to know what it is and how to correct the issue (if there is a way to). 

Any help would be appreciated. If you need to see the entire page source to figure this out, just let me know and I will edit the post to include it. 

Thank you in advance. 

PROBLEM SOLVED:

Okay, so the solution that solved my problem was to do some additional troubleshooting. I had initially assumed the problem was only with the pages containing php, however I discovered that other html pages were also affected. So, I used one of the properly working pages and copied it as a test template. I used that template to copy paste my php code into and - voila - the menus worked again! 

Just goes to show how easy it is to accidentally delete a closing div tag which is what I think I may have done.

Thanks to everyone for their help.