Hi and welcome to JustAnswer,
Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially, what tries have been attempted?
Have you tried using your computer to download the applicable software update file and then transfer to your Kindle?
Can you please try? ...from your computer, go to Kindle Keyboard Software Updates by click HERE or open "https://www.amazon.com/gp/help/customer/display.html/ref=hp_bc_nav?ie=UTF8&nodeId=200529680".Then check click on which version model of Kindle is apt for your particular model.