Users can easily fix the Kindle's critical battery error with the above methods. It is simple to fix, Kindle won’t charge. It is also vital for users to follow all instructions quickly.
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If your Kindle is experiencing a critical battery error, it may not turn on or function properly. Here are the steps to restore your Kindle:

Charge your Kindle: Connect the Kindle to a power source using the charging cable. Allow the Kindle to charge for at least 30 minutes before attempting to turn it on.

Reset your Kindle: If your Kindle does not turn on after charging, reset the device by pressing and holding the power button for 40 seconds. Release the power button, and then press it again to turn on the device.

Restore your Kindle: If the previous steps do not resolve the issue, restore your Kindle to factory settings. This will erase all of the data on the device. To do this, press the "Menu" button on the home screen, select "Settings," select "Menu" again, and then select "Reset to Factory Defaults." Follow the prompts to confirm the reset.

Contact customer support: If your Kindle is still not functioning properly after trying the above steps, contact Amazon customer support for further assistance. They may be able to help you troubleshoot the issue or offer a replacement if necessary.

Greetings,
Peter