If you experienced this issue, please make sure that your Facebook Application isn't in Sandbox Mode
To check, edit your application and disable the sandbox mode. check screenshot: http://screencast.com/t/yVvdkhYJzpGR
If this doesn't solve your issue, check Facebook App ID and App Secret on your settings and verify if you have added the correct details.
If the mentioned above fix didn't solve the problem, please send us a ticket.