Ionic not tracking sleep

[SunsetRunner]

Will someone remind me why ionic continues to not track my sleep and how to fix?  It will track for two nights then not track.  Has happened for a couple of weeks. 
Note the device is charged or fully charged. It is also tight on my wrist so it is not loose. Any tighter it would cut circulation or be uncomfortable. I have it on the same notch on strap that I have always used when it tracked properly. 

[SilviaFitbit]

@SunsetRunner It's nice to see you on the Community. Thanks for letting me know that you're wearing your watch on your wrist properly. 

There are a few scenarios where you might see your sleep pattern (which shows your time asleep, restless, and awake) instead of sleep stages:

• If you slept in a position that prevented your device from getting a consistent heart-rate reading or wore it too loosely. For best results, wear your device higher on your wrist (about 2-3 finger widths above your wrist bone). The band should feel secure but not too tight.
• If you used the Begin Sleep Now option in the Fitbit app (instead of simply wearing your device to bed). For more information on automatic sleep tracking, see How do I track my sleep?
• If you slept for less than 3 hours.
• If your device’s battery is critically low

I'll be around if you have any additional questions.