Thermostat not turning furnace on in morning

Hi have had the Wyze Thermostat for a few years now with no major issues. I have a furnace only system. The schedule I have programmed has the heat reducing at night (to 60F) until I need it to heat up in the AM (to 68F). Issues started a couple weeks ago where it was cold in the house in the AM as the furnace had not followed the schedule to heat back up. In fact, the house temps were below the night time temps on the schedule - the thermostat was not communicating with the furnace. To get it heated up, I had to manually turn off the main furnace switch and restart it. The thermostat works fine when we turn off the schedule and manually reduce and increase the temps. Electrician checked the furnace and found no issues and suggested it was the thermostat. The iPhone app is updated on my phone. Thoughts? Thank you.