Sleep Stages not showing - firmware???

[JeffMindlin]

I Just bought my son a Versa 2 and no matter what we do it will only show basic sleep data. He’s on his 90 premium trial and I’ve checked everything else - I have a Versa 2 also and it works fine. 
He posted about this a few days ago. Unless  we get a response from support very soon, I will be returning this device within the statutory period. 

[JeffMindlin]

It’s says it’s not getting a consistent heart rate reading During the night as a reason  but it shows a constant reading with no breaks.???

[Rich_Laue]

It probably then is not getting a consistent heart rate @JeffMindlin 

Let's look at the FAQs

How do I track my heart rate with my Fitbit device?

What factors can affect my heart-rate reading on my Fitbit device?

[JeffMindlin]

That’s what it says but is it new, worm correctly and heart rate shows as consistent with no breaks.