Monoprice no longer sells this item, so support from them is pretty much nil. I believe this item is actually made by Zooz, it’s z-wave plus, and it has a fresh CR123A lithium battery in it.
I have the original instruction manual, and I followed the directions by pressing the recessed program switch on the back of the unit with a paper clip to have it broadcast its Network Identification Frame (NIF). I went into HA and added a new integration, chose Add a Z-Wave device, then Search for Device (there’s no QR code on this sensor). It searched for 5 minutes before timing out. I then tried a 20-second press on the button to reset the sensor, but that didn’t work either. Has anyone had any success getting this device to work with HA? I previously had it paired to a Vera Plus with no issues. I also tried a new one, fresh out of the box, and couldn’t get that one to pair either.
I have a brand new ZWA-2 that initially wouldn’t connect to the HA Green, but I fixed that connection with help from tech support by changing the Device name in the Z-Wave JS UI config.