Android : The developers of this app have not set up this app properly for Facebook Login error

This is a common error that many people get, I have already made the app public in the status & review ( changing the status from off to on )..but I still get the error when I try to log in using my android app.

I have added both the release and debug hash keys , the problem is definitely not there, where could it be the error? can somebody help?

Regards