apps constantly requesting permission to access camera, photos, microphone, contacts

I'm using a iPhone 6s w/ iOS 9.2.1. In the last couple of days some of my apps (Garmin Connect, Snapchat, FB Messenger, Instagram) have frequently been requesting access to my camera, photos, microphone, or contacts (depends upon the app which they request access to). Almost every time I use these apps they request permission to access even though they've already been permitted to have access. My restrictions are off. The apps will show up under the privacy settings as having permission to use the camera, microphone etc, but then later that permission disappears. Everything was working fine until 2 days ago. It's kind of a nuisance to constantly have to grant permission. Anyone know how to fix this issue?