Had one case of a “stuck” Zooz motion sensor here, as well, just last week. I wrote it off to a “lost message” from the device not making it to the appropriate hub driver. Everything was still working and simply walking into the room started a new motion cycle and all became well.
This behavior isn’t new to me: it happened in the past with other devices, including a (different brand) motion sensor. In 2017 one of three door sensors reported door “open” at our second home 1500 miles–I ended up writing a special DTH to see if the door was okay. Here’s what I ended up doing to prove the door was closed, if you’re interested…