MVC 4.0 Facebook Integration Login Failure

Hi:
 We are integrating Facebook in our portal. I have created two APPS in facebook developer account using my facebook account.
The App i created for my localhost works fine. However the app I created for the staging server is not working.
After facebook login, it redirects to /Account/ExternalLoginFailure
May I know the reason for this?
Do you have a paid service so you can look into this issue?
Vas