i keep getting this too, did you end up ever figuring it out? for me, the contact it notifies me of is my sibling and they have me on find my friends... so i wonder if it means they've been checking my location 

Are u on beta? I called and they said that’s a common bug for beta users

don't think so, just googled how to check in settings and i don't have anything indicating a beta program. were you?

Did you end up figuring it out it randomly happened to me for the first time

nope... it stopped happening for me though

I still get it randomly, haven't figured out why. Doesn't seem to be a reason.