For some reason most of my Fibaro devices, RGBW Controllers, switch relays, smoke alarm, have just stopped working. They appear as unreachable in the developer tools when tested. I have restarted Homey and re-installed the Fibaro App with no success. Raised a case with Athom but awaiting response. My thoughts are its an App issue so wondering if others are experiencing similar problems.
Can you post ZWave part from developer interface?
Usually it happens when some more is broken, have you tried Heal?
It seems to be more than just Fibaro, the problem is related only to Z-Wave Network devices. When I run the heal command on a number of devices it comes back with timeout error, as it does when I send a Test command.
No idea without details from Homey Developer Tools