Half of night, sleep stats are greyed out??

[Fit2]

Most nights, my stats show up where the first half of the night's graph (showing awake, REM, light and deep sleep) are greyed out, and only from about 2 a.m. on is it in dark blue.  Is this saying something about sleep quality from the first half of the night?  Does anyone know what that means?

[mb2706]

Sounds like you have 2 sleep records, the grey 1 should be selectable and give you the sleep insight. you must of woken up in the night enough for the watch to think you are awake, I've had this a few times