This problem has occurred since I got the phone a few months ago.
I *do not* want it to vibrate in any mode whatsoever. I love the phone but hate the honking sound of the vibration and it's very disruptive in a quiet setting.
I go into Apps/Setting/Sound/Vibrate and toggle NEVER.
After this it sometimes stays quiet for a day, but it sometimes honks at me within seconds with a notification of some kind. When I go back into the Sound settings again, sometimes it's still showing NEVER but sometimes it's showing "only when on silent" so something has changed the setting.
Never means never-ever and I'm tired of being startled by it.
Do I have to go into each individual app and tell it not to send notifications, or notifications w/sound, in order to make this stop? I would think the phone settings would rule the individual apps and do not relish the idea of having to diagnose everything that's triggering vibration.