Charge 5 won't work unless it's connected to the charger

[Vynch]

I’ve had my device just over a month now, and today it just suddenly won’t hold a battery charge at all. 
I can connect it to its charger just fine, screen will light up to indicate that it is changing, and can go all the way to 100%. But the instant I take it off the charger, it immediately dies. Reconnecting the device to the charger will display 1%. 
I’m going to assume that the battery has had it, so what steps do I need to take to rectify it? 

Moderator Edit: Clarified subject

[SharonE1122]

Hi. I am having a similar problem. Had the tracker a month and the battery is running down quickly. I was at 34% yesterday afternoon and it was dead this morning when I woke up. It has since recharged to 100% but not sure how long it will last. How do we get a refund or a replacement tracker?

[RiekoC]

Contact Fitbit support, preferably via Chat when they're available. They will walk you through a series of troubleshooting procedures. If none of those procedures return your device to normal operation and they confirm that your device is still under warranty, they will send you an offer to either replace the tracker/pebble or a discount to use on a different device. FYI - The discount is on the full price, even if the device is on sale on Fitbit's website.