This has been posted before, also by me and this is still an issue. It's even worse than ever! I'm getting detailed sleep and movement readings while NOT WEARING the watch.
I know some people (will) say (again) I should ignore it, or set sleep time to 1 minute. Did that, 00:00 - 00:01
However, Garmin somehow figured out a way to let their hardware/software measure my sleep while I'm sleeping, NOT wearing the watch, which is lying about 2 meters away from my bed OR it is a bug. I'm pretty sure this cannot be a feature as features are intended functions.
Check the pic for the readings.
Fyi: during these readings I took the watch off at around 11 and put it on around 9.
Why I'm concerned about this? I'm pretty sure sleep measured sleep data is used to create a health picture of you.
Will contact Garmin about this.