Why are my FaceBook events not showing up in iOS Calendar? My FaceBook events are not showing up in my Calendar on my iPhone 4 running iOS 7. Sometimes I can get them to show up by going into Settings -> FaceBook and turning Calendar integration off and on. Then a while later, I'll find that new FaceBook events are not coming through again.

The Calendar has the FaceBook Events option ticked.

Why is it not working properly?

My iPad 3 running iOS 7 doesn't appear to have this problem.
I had this same issue. iPad (and Macs) showed the events, but iPhone did not. I finally went to Settings > Facebook and clicked on my account name, then cleared password and re-entered. After it verified, the events showed up in Calendar app.