New One 6.64 not working

[meemsme]

I just opened a brand new Fitbit One and updated it to 6.64. However, it is now no longer responsive.

I've tried

• pressing the button when it is charging, no response
• unplugging the device from the charging cable and holding for 10-12 seconds, but still a black screen
• the phone app indicates the battery is still full

Please advise. Was really looking forward to this to be functioning. Thanks! 

[Netsrik95]

Mine has stopped counting steps. Display is there, just says 0 steps. If my chance it starts to count and I upload, it will reset to 0. Very frustrating. I love(d)  my One

[Ubermich]

My borked One is the second One I've owned. Because I hate wrist things,

It was new in packaging. Updated to 6.64 and it borked, With its brand new battery. Shows full battery charge and FITBIT 6.64 and will sync with both the iPhone and the Win10 Desktop app. But as soon as it's out f the charger - it's a brick. And yes, I have tried the hold button for 10-12 secs while in the charger then remove from charger and hold button until unit turns on.

It doesn't.

In the absence of a working One, I am using a freakin Flex that I bought a One-like silicon holder for. As I said, I hate wrist things.

[Rich_Laue]

Sorry @Ubermich there really isn't such at omg as a new one, even if it hasn't been opened. 

It glass been several years since the one was last manufactured and there is no telling what the state of the battery may be. 

[Lmw814]

I too, am having all the issues described with lost of charge in less than 24 hrs and not syncing on my ONE. I've had it since 2012. I thought my issues were due to age of the device. I had a brand new ONE that was never opened. It is from 2017. It too is having the same issues a my original ONE.

I love the ONE as it is "hidden" while still tracking. I received a Versa2 though a fitness plan from my employer but not thrilled with giving up my Garmin Forerunner 35. I will continue to try and reset my ONE. Come on FTBIT and help those of us who love the ONE.

[Rich_Laue]

Your 2 year old never opened One may still have a battery issue since it has been sitting around for more than 2 years. 

[Williger]

@Lmw814 I'd agree with @Rich_Laue, having a "new" tracker sitting stored likely will have a dead battery. Been in these forums for a while and many people who bought a spare or bought "new/old stock" from eBay have had this problem. Hopefully yours resets, otherwise your only option is replacing the battery yourself (they're $10 on eBay, takes a hair dryer to open and a soldering iron to install), or buying the Inspire with clip for a similarly discreet option. Good luck!

[mychamp3]

I have the same problem, went black, plugged it in to charge and it showed fitbit6.64 and is now recharging. However, it is connected to the fitbit app on my phone and it is showing my steps etc on my fitbit app on the phone. They need to come up with a replacement for the fitbit one if they are no longer selling it. Very poor customer service. Can't get it to do anything. Where do you buy a new battery for this thing to replace old one seeing so many of those responding to us say to replace the battery?

[onegreatwolfe]

Same with mine, I had a spare, no one in the family would use so after losing my old one I hooked this one up and it updated to never work again. Same issue as everyone else. Last night 3/25/2023 right out of the box.

[onegreatwolfe]

As of 3/25/2025 new out of the box. Fully charged I finally got it to replace the old one I lost. It said it has to update, it did. After that it would not sync. It will not show a display and I can't get it to do a restart. Even the one I lost had not been syncing right after the new updates. I like Google but they are really destroying Fitbit. For now I have to keep trying as I can't afford to buy a new tracker. Sadly I really liked Fitbit it was my first tracker with an app.

[onegreatwolfe]

The ultra came with an Xbox I bought my children. I used it till it completely fell apart, I mean I fixed it, taped it, even put it in a medicine bottle to keep it safe. I finally had to let go and buy the one 🥴

[RChobby]

I cannot get the firmware to update, my “one” is stuck at 6.6. Would be fine except for the constant “please update tracker” messages from the iOS Fitbit app. Annoying. 

[Ninerz4life]

HA! That’s the response I was looking for I too have been a long time Fitbit One owner with a vast bone yard of dead Fitbit Ones. Was wondering why my newest one would not update and one new out of the box with 6.64 dead after the update just as all complained about. Fitbit is preventing the update on purpose to prevent damage to the already working devices with 6.60. Something about the 6.64 update out of the box zaps the device dead! But just as you said @RChobby  the annoying pop up continues.