For 3 nights in a row, my vivoactive 5 has not detected the sleep start time. It detects 1 a.m. instead of 11 p.m. I didn't have this problem with my Venu Sq.
Hello!
1) Are you wearing the watch for the 2 hours prior to your sleep period?
2) If you review your data for the 11:00pm. - 1:00am time period
I finally asked for a refund on the Vivoactive 5 because it still failed to detect when I fell asleep several nights later. I'm disappointed.