Error messages include warnings such as "Supervision Failure".

The panel regularly checks in with its network on a schedule defined in the terms of your service. If the control panel has a communication failure between 2 check-ins, your remote service will not know that connection has been lost.

Check the panel’s power supply, cellular connection and internet connection. Remember that internet connection requires working Wi-Fi. Make sure your router (or other Wi-Fi access device) has AC power and that the access device itself has a working connection to the internet.

If you can't restore the connection(s) or if the problem recurs, contact your security professional.

It is always best for your control panel to have working cellular and internet connections so that one can serve as a backup if the other fails.

Also, please see the FAQ What does "Not Ready To Arm" mean?