Usually, a firmware update makes a gadget better, not worse. That’s not what users of the Fitbit Charge HR are experiencing after the device’s most recent firmware update, though. They report that their devices will only stay charged for anywhere between three days and a few hours, when the battery lasted longer before the update.

Reader Alex, who alerted us to this problem, happens to live in a household with multiple Charge HR owners, and noticed the difference. “Three members of my household are only seeing 2 days battery life after the firmware update,” he wrote to Consumerist. Alex and his pals aren’t alone: users on Reddit and on Fitbit’s support forums report the same problem after the very same firmware update.

“Your tracker’s battery should last up to 5 days,” Fitbit says in the company’s help document for users having battery problems. The key words there are “up to,” since battery life can vary according to what you actually do with the tracker while using it. However, a wristband that’s meant to track movement and sleep probably isn’t meant to need charging every few hours, and battery life suddenly plummeting is a bad sign.

We contacted Fitbit about users’ experiences and whether they’re connected to the firmware upgrade: we’ll update this post if we hear anything back. If you have a Charge HR or other Fitbit device that has suddenly lost battery life after an upgrade, let us know!

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