If the message "SYSTEM IS OFFLINE" is displayed please perform the steps below:
  1. Make sure the WiFi network is working, eventually restart the router
  2. Log out and log back into the Resideo application
  3. Restart the thermostat (unplug or remove it from the wall plate for 30 seconds).

If these steps do not solve the issue, please follow the instructions in the video below to reconnect the thermostat to the internet.