ZWave switch "unavailable" but shows active on the map?

I have a Zooz switch that shows on the map, but in the status page, it shows a red icon:


Also in Developers Tools/States the entities are all unavailable.

It had previously worked but may have been unplugged for a couple of weeks.

Should I remove it and rescan as a new device?

Try to ping it now that it is plugged in.

Yes, it pings:

Ok. It should not longer be dead then? You’ll want to reinterview it as it is reporting unknown manufacturer.

Thanks- Interview did the trick. What does Interview do and why would a device need to be re-interviewed?

Interviewing is a process that a controller uses to determine the capabilities of a device. For example what sensors it has and who manufactured it. Interviewing is typically done at inclusion time and should be redone after firmware upgrades. So in practice it should not be needed.