Got my Vivofit 4 about 2 weeks ago, and it seems to not always track my sleep...

I miss this functionality, too. Used to have it on the Jawbone. But then again, even the now defunct Jawbone was able to correctly track sleep without use intervention after the first update of the UP3 (almost 3 years ago). It is shocking that Garmin can't really do that right on any of it's devices. And don't even get me started with the inability to log naps...

Anyway, I just edit the starting time every morning. It rarely misses the waking up time, though. Just the bed time.  UC Browser SHAREit Appvn