Have an Aeotec Z-Wave stick in my QNAP NAS which runs Home Assistant as a VM. That works.
Then installed a Combee 2 USB stick to take care of Zigbee. After plugging it in, all the Z-wave entries in Home Assistant changed to “Entity not available.”
I removed the Combee stick but no use… all the Z-Wave devices remain in the errored state. Don’t know how to remove them, don’t know how to fix them in place (have tried various things and searched for this but so far, no solution).
One step forward, two steps back.
Sometimes when you add USB devices the paths to the hardware gets reordered and then you the connections to the devices on those changed USB device paths.
You can try a few things, like remove the new USB device and restart, move the old device around and get that to work again in another port. If you are successfull, then you need to figure out which port to add the new USB device into, so the old device does not get shifted by the reordering.
Sometimes the easiest way though is just to accept the reordering and start over by readding the devices in HA and correct paths.