How do I get the "Login with Facebook", "Login wiht Twitter" to work?

How do I get the "Login with Facebook", "Login wiht Twitter" to work?

"Login with Facebook" just doesn't respond - After clicking the payment button link redirecting to paypal page with out asking fb login.

I Tested only for FB.

Pay Per View -> API Settings followed changes are done

"Accept API Logins" - checked

"My website already uses Facebook" - unchecked

Used FB API Id

need to do anything else?

Regards,
S