Samsung galaxy watch 42mm.
Sleep tracking does not seem to work.
The last 3 nights I am recorded as having no deep sleep and less sleep than I would have thought.
I have HR tracking on always with goodnight mode and do not disturb.
Think it's a samsung software issue. Have a similar problem with sleep (and steps, and calories, and staircases, and......).
There's plenty of people complaining online about this.
Mine works fine - have you tried without the do not disturb and Goodnight mode? I appreciate that is a bit contradictory though but it may help in isolating the problem?
Also, is your watch strap secure? If i wear mine loose then sometimes the results are erratic.
So, I have the same Issue. I think it has something to do with the the HRV-Measures. What I can see is, that during the day it measures my stress-levels without problems, but during sleeping it is deactivated somehow, so no data were recorded for Stress-Level. But Stress-Level measurement is set to "always" and HR-measure too. For HR-measures I get continuous data during the night.
I will try this evening with not activating night mode. Hope it will help...
So I used now only not disturbing and airplane-mode without sleep-mode and same behaviour. So I hope, Samsung fixes this bug in the near future. Quite Disapointing... It seems, the developers don't use the watch on their own. They just code and test it inadequately...
Same problem for me, didnt work from the beginning on, I am thinking of returning it to the vendor, this is one of the features which i consider mandatory....