My husband just messaged me with a screen shot of a notification he says he's been getting "often". It says "iPhone Is Not Activated" and we're trying to figure out why it's happening, how to fix it, and how to keep it from happening again. He's currently using an iPhone 6S and I'm not sure if he's been keeping the OS up to date.
I currently have an iPhone SE and this is not happening to me.
Thank you for any assistance, it's much appreciated.