Have had this issue too. It's plugged in so not a big deal but still annoying as it goes off right by my bedroom window.
Also, I have Smart alert settings for people only and I still get bugs and spider webs triggering it at like 30% sensitivity
I should add that mine seems to do it when I open the app to go in and arm another base station the floodlight is not connected to.
Soon as I open the app, the motion guy goes off and the light turns on. There's nothing triggering it as it does this every time at night when I open the app.