Sometimes my sleep pattern has a gap where the watch shows nothing. Last night I went to bed 11:30 and my watch (pulse HR) showed sleep until 3:09, but it it labeled this NAP. There was them a period of nothing recorded until 4:19 i.e just over an hour before restarting to show my sleep pattern. This hour, I was in bed and asleep. The heart rate monitor continued showing a normal trace with no interuption and the steps monitor showed no steps for the period. My sleep score indicated 21 for the period 4:19 until I woke up around 8:30.
Any ideas how to explain this.