I added the devices and they were working fine, but now there are gone from the app, what happened?

The device settings are all saved to the app and cloud automatically by the app. If your phone is not connected to the internet while you are adding the devices, and your phone becomes damaged or crashes during the process, the settings may not get backed up to the cloud.  In almost all circumstances the app will prevent you from logging out while in this state and preserve your settings until internet connectivity is restored.

In the extremely unlikely circumstance that the settings are lost, it may be necessary to perform a device reset and add them back into the account.