Fitbit Blaze sleep will not update correctly

[CyberB]

Yesterday (2/8, Friday) Blaze recorded two sleep periods for 2/07 (7:15-~11p) and 2/08 (~1-7:17a), but didn't total them. As I usually do, I deleted the second entry, and edited the first sleep entry to record the actual rise time as 7:17a. Surprise, the update entry CHANGED to showing 2/06 to 2/07 with the new times (these dates had already been recorded so it couldn't be updated)!

I've reset the Blaze, updated the Win10 App to v2.40, charged the Blaze, and was able to edit the surviving sleep entry to show 7:15-11:59p; but if I update this to 12:00a the dates revert to 2/6-2/7 again.

I also changed the rise time to 7:30p on 2/07, and then back to 11:59p but couldn't edit rising into the am (again, the dates reverted to the prior day). This cost me all but the limited sleep detail...

Finally I deleted the surviving entry, and clicked "Add an entry" for the correct times for 2/07-2/08 which was accepted (but with only limited sleep detail). The result was a total of 10h33m with several restless or awake periods but nothing otherwise very strange.

So, why does Fitbit's app "pencil" for edit sleep data keep changing the date for entries?

Moderator edit: Updated title for clarity

[FerdinandFitbit]

Hi there @CyberB, welcome to the Fitbit Community Forums! 🙂

I'm sorry to hear that your Fitbit Blaze is splitting your sleep logs in two chuncks. Thanks for your efforts in trying to get your tracker to work correctly. I'd like to help you out.

In case you've not tried some of the following, I'd like to share a few suggestions:

-Make sure that you don't take your tracker during the night as this will interrupt your sleep tracking.

-Do you remember by any chance being awake during the night? If so, that would be the reason why you see your sleep log like that. Even if you don't recall being awake, you might wake up in the night for short periods of time that are often long enough to interrupt your sleep tracking.

-Make sure that the Blaze is snug on your wrist when you wear it to bed (the lights shouldn't be visible).

-Try sleeping with the tracker on their non-dominant hand.

-If your sleep sensitivity is set to Sensitive, rever it to Normal. See the instructions on how to do this here.

Hope this helps. Please, let  me know if you need more help!

[BrainWaveCC]

Over the past 2.5 years of owning a Blaze (two Blaze devices, in fact), I've found sleep tracking to be quite iffy.

My first Blaze was reasonably good about tracking regular sleep, but not deep sleep.  It tracked deep sleep on its own less than a dozen times total over a two year period.

My second Blaze has already notched 8 or 9 deep sleep events over the past 5 months, but only one of them was for a realistic amount of time (7-8 hours).  Most were between 4 and 5 hours (on nights where I slept soundly) and half of those were in chunks (correct sleep start and wake times, with a huge gap in between).

I went through about a 3 week period where I did all kinds of tests every night to try to see if it was something about me, or the device.  I even tested with my wife's Charge2 device.   The short answer (for me) is that Blaze tracking of this statistic is flaky at best where deep sleep is concerned.   Regular sleep/wake tracking is around 90-95%.  (Translation: some abnormalities, but not enough for me to do serious testing)

So, I have grown used to not having the deep sleep info.  Ironically, the people in my home who can get that info regularly, don't care about it.  I do, but can't get reliable data from the device, even though some other devices are more accurate for me.