My Fire HD10, less than 2 years old has stopped working and I am pretty certain the battery is completely dead. I have been told by the Amazon support team that batteries cannot be replaced and are not supplied separately. Is this true? I have taken the back off and it's pretty simple to remove the battery.
yes it's true - Amazon does not repair Kindles/Fires and there are no official replacement batteries or repair facilities. You could google and fine a source, but make sure it's the exact same battery, and have a cell phone repair place replace it or do it yourself (there are lots of videos that show you how to do it).