Thanks for posting here in the Google Nest Community.
A blinking green light near the top of your Nest thermostat’s display means that it’s updating the software, starting up, or restarting. Typically, this will only last a minute or two. Once your thermostat has finished starting up, it'll turn on so you can use it.
If the light blinks green and your thermostat is unresponsive for more than 15 minutes, it may have frozen during the update.
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