Could Not Follow Redirect Path

I was debugging open graph for my new website and I have the following error:

Could Not Follow Redirect Path and URL returned a bad HTTP response code.

https://developers.facebook.com/tools/debug/og/object?q=http%3A%2F%2Fwww.webcilento.com%2Fsite%2Feventi%2Ffiera-di-prova.html

This error occurs only in calendar section (http://www.webcilento.com/site/eventi/fiera-di-prova.html)

I'm using Joomla 3.2.1

Any ideas?