The whole day went by, and as I was sitting in the parked car about to get me and A. out for her swim lesson, the phone rang and it was S., the shop guy. He walked me through the settings I needed to access -- a dead simple change and I feel slightly foolish for not figuring it out on my own, but he didn't make me feel foolish at all, just said it probably got reset by the software update -- after making sure I was in the car, not currently driving, and had a minute.
I really have to remember the importance of Names. I don't need to know the names when I'm interacting with the person, but if I can manage to remember someone's Name, I can get to them again via other random people who answer phones. I'm not sure why it has taken me this long to learn this lesson, but hey, better late than never, amirite?