* In the Facebook application, what is the value for 'Category'? You can find this in your app > App Details > Category option.
* How have you configured your request in the backend?
* Can you give me a specific URL where you're added the request on the front-end?
Also I see the following warning from the Autotune Error Check for your page. If you have access to the site restricted, it's possible that it could cause Facebook some problems. Could you try enabling access and see if that helps resolve anything?
Checks performed on: YOUR_WESBITE_ADDRESS
Error: Could not fetch page. Server returned:
Error Code: 401 - Unauthorized Access. If you have a username/password requirement to access your site, please disable it.
-Melissa