This isn’t SmartThings, but for Nest thermostat owners in the US, there seems to have been an upgrade to the devices yesterday that has left several of us with drained batteries.
Remember, if yours is completely drained and unresponsive to manual manipulation, you can charge it using a micro- or mini-usb cord to your computer for about an hour and it should work at that point.
Bad time of year to do software updates on a thermostat in North America.
I’m having a ‘C’ wire installed tomorrow. Tired of the Nest power stealing hack.