Completed annual maintenance on a 2019 Goodman air conditioner. All electrical and mechanical components check out at this time. Technician spoke to customer about possible thermostat issue. Customer states the after 24 to 48 hours the thermostat resorts Back to 50° in the cooling mode. Technician went through the schedule on the thermostat and found nothing. Customer stated if the problem continues they will call the office back and set up a date to change the thermostat. Current thermostat is a nest.