My machine is not showing how long it was on

[Keepsleeping]

I have been struggleing to use my machine and I want to monitor my usage. However, when I look at the display for how long it was on for the night before it say 0 hours. Any ideas? How can I fix it

[ems]

You have to check it before 12:00 noon. After that time it goes back to 0.

Edit: The data hasn't disappeared, it stays stored in the machine. However, you can't see hours of use after noon time.

[RandyJ]

If you want to check hours of use for the night before after 12pm, press Info to display Sleep Quality screen. You can hold down the two rectangular buttons (info & setup) until the screen flickers (2-3 secs). Then turn knob one click to the right. If "1 day" is displayed on the Sleep Report, you'll see hours of use for previous night next to Used Hours. If "1 day" is not displayed, press knob down once to highlight Period, then turn knob left or right to change.