The Nest thermostat used to automatically switch between home and away, but that feature has stopped working over the past few months. Recently, I found that it detects my departure from home and will switch to ECO mode, but when I return home, it shows and confirms that I am Home on the app, but the mode setting is still on ECO mode. I need to manually switch it back to the normal mode. I have checked everything on the app but found nothing out of the ordinary - I've had the same settings for the last three years. It's a 3rd generation model. I have tried the following without any success:
Next step: return the nest?
I have noticed the same thing over the last month. There must have been a change. Home/Away assist confirms that it knows I came home, it’s set to home, but I’m still on ECO. Only thing I noticed different is that I had manually set the thermostat the previous day. But, it should have resumed automatic mode within a few hours. It had in the past.