We bought a google nest thermostat (pro), and had it in a box for a couple of months before opening (we had been planning ahead for a new HVAC). Once opened, the device did not work (heats the house, but device constantly rebooting and display off). There is no customer service line, or way to return the product. Or more specifically, you can write online a request and 'they will call you back'. The never do (no record on our mobile), but the answer after a few weeks that they did and could not reach us (without leaving any message of course). This has been going on for months... they basically are just giving us the run around.