I tried multiple times to update to the new 3.3.20 software but every time I'd get a "Software update failed. Tap for more details." notification in the app fairly quickly. After tapping for more details, there's no error message. I eventually realized that it's because I had car seats installed in the car and the seat belts were latched, and as a result the car would not update. Just posting it here in case others run into the same issue in the future.