They natively work as Zigbee repeaters work great as so. You need a custom DTH (Device Type Handler) for them to work as Z-Wave…(at least the last I knew). If you installed the 3210-L plug to work as a Z-Wave repeater and did not install the custom DTH then you its not repeating Z-Wave…Might want to check on that first.
Wish I would have know this before I invested in 4 of them! Given the issues, I must agree though.