Shelly z-wave trouble turning off (maybe ZEN51?)

I have a Shelly Z-wave 1pm controlling a light fixture. It reliably turns on via my automation schedule at sunset. However, recently it stopped turning off at midnight. This was working great until recently (there have been some ZWave JS updates, and IDK if that is the culprit).

HA indicates this is not my Shelly, but a ZEN51 - and that may be correct, but I can’t open the fixture to look rn. I did have one of those lying around when I wired that fixture, so maybe I misremembered and used that instead!

I still don’t know exactly why it turns on perfectly, but refuses to turn off, but I tried turning it off manually one evening (via my HA dashboard), and what happened was it toggled off, then back on. I tried this again, and it seemed to toggle back-and-forth a few times - as if someone was flicking a switch up and down randomly!
Has anyone else seen this and know of a fix or workaround?

Thanks.

EDIT: I’m using a Zooz usb stick for controller as follows: ZST39 LR by Zooz, Firmware: 1.20. Maybe it needs updates too?

Here’s the log. I can post the automation, but it’s simply to turn each of the three devices off.

Power cycle the device by throwing the breaker.