Hello and sorry you're having problems. Sometimes this issue can be caused by the Kindle needing to be rebooted. I'm not sure if you've tried this yet, but if not please first give the steps below a shot before moving towards replacing the battery:
To do this, simply press and hold the power button on the Kindle for 25 seconds, then release and wait a full minute for it to reboot. If this does not cure the issue, oftentimes the reset procedure needs to be repeated several times for it to force a reboot.
If you're still having the same problem after the reboot- then the battery can be purchased at the link below for your model. BONUS: There is also a video that outlines how to make this repair yourself, and the site also sells small tools that are handy for replacing the battery.
NOTE: If you need further assistance let me know. Please do not forget to click a POSITIVE RATING before you go- as it's how I am credited for my work. You can follow up at any time, at no additional cost.
Do you need further assistance with this?
The link I posed to you- shows a VIDEO which outlines exactly how the Kindle is opened and the battery replaced. Were you not able to see it? Here is the link again- click on it and view the video. As I had mentioned above- special tools are needed AND sold at this link:
NOTE: Please do not forget to click a POSITIVE RATING before you go- as it's how I am credited for my work. You can follow up at any time, at no additional cost.
Please also scroll up the page to see all replies if you are missing the link I posted.