First Night, No Body Battery

I have exactly the same issue with a Fenix 6, I'm sending it back if this doesn't work as it renders it useless, come on Garmin please respond 

Hello!

Your Garmin device needs a learning period to provide accurate Body Battery readings. For new devices or those reset to factory defaults, this typically takes 5-7 days. During this time, your Body Battery might temporarily show 5%. Resetting the watch will restart this learning period. Expect normal Body Battery function after about a week.

Similarly, some Garmin devices occasionally recalibrate Body Battery and all-day stress tracking. If this calibration is lost, your Body Battery may drain to and stay at 5% until enough data is collected to re-establish your physiological baseline. This re-calibration process can also take several days.

If you are outside the learning period and still experiencing this, please contact Garmin Support for the most efficient and detailed assistance

… plausible

Hello, one little bit of extra information which shows this isn't the issue, it worked perfectly the 1st night I put it on, the following 6 night it didn't work

Except it worked the 1st night for me !

I just called Garmin support and they confirmed to me what is happening as they looked at my data, the watch is overriding the data from the sleep index, therefore it isn't showing anything, they have raised the case with their engineers, I'm returning the sleep index as it is pretty much useless without this working, they couldn't give me any idea of when this will likely be resolved, but they confirmed it is an issue. 

Same here - index Sleep Monitor since Sunday and a Fenix 6. I put the Fenix into low power mode at night and place on a charger, wearing the Index Sleep Monitor. In the morning, Body Battery initially shows a blue "rest" graph when the ISM syncs, but no digits. Then I switch the watch out of power saver mode, it syncs and the blue "rest" graph turns grey "active", but I do then get a body battery value (95 this morning - but states charged = +0). It's definitely the Fenix sync that seems to screw the graph and charged number up - my wife also has the ISM and it works fine for everything, she has an Apple Watch.

Hello All!

We have other reports of this and are actively investigating.  Please let me know if we have your permission to reach out to you via private message, we would like to collect some additional information. When we know more or have any updates to share, I'll be posting to this thread.  Thank you in advance for your patience with us while we conduct this investigation.

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