This thermostat is without a doubt the worst one on the market. They tried to make this thing so smart it sucks. No matter how many times I change the settings some how it goes back to ECO mode on its own. Which that ECO mode all it does is not go to the temp you set it on?! This product sucks.
Thanks for reaching out. I'm sorry to hear that you're having an issue with your Nest Thermostat. To isolate the issue, please try checking the Nest Energy History to see the reason why it's going to Eco automatically. You can click on this link to learn about reading your Energy History.