I\'m using phonegap facebook connect plugin (https://github.com/Wizcorp/phonegap-facebook-plugin) for Facebook Authentication in app. It was working till today morning. Now
I had the exact same problem which popped up last few days or so. I fixed it by generating the respective platforms in the app's settings. Note that I only had the general settings before and it worked, but something probably been changed recently.
good luck!