Hi again puneet84pandit,
Thanks for giving those steps a try. If you tap Settings and scroll down to Facebook there, do you have All Photos or Selected Photos enabled for FaceBook?
If you're not seeing that option, or still don't see Facebook listed in Settings > Privacy > Photos after making a change there, we suggest reaching out to Facebook support for further assistance. They'll be the most familiar with their app and service, and any other steps specific to the app that made need to be taken to enable photo sharing.
How to contact an app developer
Facebook Help Center
Cheers!