Missed call notification suddenly appears a day later
I have an iPhone 6 at current patch level on the AT&T network. Every once in a while I'll look at my phone and discover that there will be one or two missed calls from as far back as one or two days ago. More often than not, they're robocalls from area codes where I don't know anybody. I probably check my phone every hour and I have the phone next to me all the time, so it wasn't like I really missed a call when it came in. I suspect that somehow the callers are somehow aborting the call even before it could ring at my end even once and they're forging the call time.
Does anybody have this experience? Are my suspicions correct about the robocallers probing the phone network trying to find legit numbers for later calls? Is there any way to stop this?
iPhone 6, iOS 10.1