Sleep stages not showing

[TanikaRenee]

My Fitbit has done sleep stages since I got it and for some reason it hasn't been tracking with sleep stages. It's tracking the old way and I haven't done anything different. I need the sleep stages cause I'm trying to track my sleep for the doctor. Anyway to fix this?

Moderator edit: Updated subject for clarity 

[SilviaFitbit]

It's great to have you here @TanikaRenee! I would like you to make sure that you have updated your Blaze properly. Also, you need at least 90 minutes of sleep in order to have sleep stages. You can learn more about it by checking What should I know about sleep stages?. 

Fitbit estimates your sleep stages using a combination of your movement and heart-rate patterns. When you haven’t moved for about an hour, your tracker assumes that you’re asleep. Additional data—such as the length of time your movements are indicative of sleep behavior (such as rolling over, etc.)—help confirm that you’re asleep. While you’re sleeping, your device tracks the beat-to-beat changes in your heart rate, known as heart rate variability (HRV), which fluctuate as you transition between light sleep, deep sleep, and REM sleep stages.

Hope this helps. 

[TanikaRenee]

I know how it all works. Which is why I'm wondering why all of a sudden it's reverted back to the old sleep tracker. Past three nights it has tracked my sleep the old way instead of sleep stages and I haven't done anything different. Everything is updated.

[Robhuff46]

My never work, and yes I try everything Fitbit suggested.

[Scog86]

Hi mine has done the same thing, updated, charged, tight on wrist and sleeping 6+hrs. But still old way two night in a row now