This is nuts. I have two NEST thermostats, one upstairs, one down. I can add one of them with the NEST app, but not the second one. On the Google Home app, scanning the QR code just crashes the add device screen back to the home screen. How the hell does something like this happen? don't most people have at least 1 or 2 thermostats? I mean, this shouldn't be this hard. I've been trying to add them for the last 4 hours. Any ideas one what to do? They are all three (phone, thermostats) connected to the same wifi network and working fine otherwise.