Here is what you need to do:
1.) Visit the applications section of your FaceBook account and delete the app
2.) Login to your Dashboard and into Facebook in the same browser
3.) Click on Manage social media until settings and click AUTHORIZE next to FB and give the app ALL permissions - make sure posts are public.
You will be all set after you do this.
Here are the scenarios where you will need to do this:
1 - If there is a warning message on your Dashboard about missing permissions
2 - If you create a NEW group or event and it is not showing up (Facebook is just slow)