I have been replacing some finicky Aqara door and window sensors with Zooz Z-wave units. I have encountered the same problem a couple of times. I don’t have enough Z-wave hardware around to know if this is a Zooz problem, a Home Assistant problem, or a Z-wave.js problem.
I can add a door sensor without issue. I open Home Assistant on my phone. I use the phone’s camera to take a picture of the QR code inside the sensor unit, everything is fine.
If I change the first sensor device’s name (and entity names) in Home Assistant, I can do the same thing and add a second unit with no problems.
If I don’t change the first sensor device’s name and try to add another identical sensor device, things go awry. I snap the picture of the second unit’s QR code and the add device wizard says everything is fine, but the device either never shows up or only shows up as “node x” and is unusable.
At this point I have to go the Z-wave integration page, click Configure for my hub, remove the entry for the second unit in the list of “Provisioned devices” and factory reset the sensor.
It seems like “the system” should be able to just create a second device called “Open Close sensor 02” or something like that instead of just not working.