In general the vivosmart correctly detects my sleep time. But sometimes it occurs that later during the day, the device (or Garmin connect?) makes a correction that is completely off. Yesterday for example my sleeptime was initially detected as 23:00 to 6:00 with a total of 7hrs of sleep. Later it was changed to 17:53 to 22:17! This is just absurd, it is totally off my normal sleeptime in my user profile (23;00 to 7:00).
This has happened more than once.