I am having the same issue with Nest.
I have 2 devices. Regular thermostat works fine for other floors in the house. Nest controls upper 2 floors. Stopped heating on schedule on last few days. Can't override. Next option is to put original thermostat back on the wall as we are down to 59F
Thanks for reaching out. I'm sorry to hear that you're having an issue with your Nest Thermostat. I'd love to know more about this and I have a few questions:
Looking forward to your response.
I wanted to check in and see if you managed to see Edward's post. Please let me know if you have any questions from here. I would be happy to assist, and make sure you are good to go.