Hi Marvin,
Sorry to hear about your switched heating/cooling! That must be uncomfortable to deal with. I'm happy to look into this issue for you.
It's a possibility that your thermostat's wiring is loose or disconnected from a terminal.
We do have a guide to look into with troubleshooting steps after looking into your HVAC symptoms. However, without knowing the specifics of your particular system, I'd suggest contacting a
Nest Pro to come and take a look, especially if you're unsure of what caused this switchover.
Hope this helps! Let us know if you need assistance with anything else. 🙂
-From Ai, Community Specialist.