Since you have tried all the rights ways to access the economist,
you can try this browser extension : https://github.com/iamadamdev/bypass-paywalls-chrome
works for chrome and firefox.
do subscribe once they have sorted their IT system out.
Kindle or Kindle Fire?
My public library gives me access to all the digital copies for free (well, $5 for the library card plus my taxes...) and they do it through the Zinio app which you can get for Kindle fire.
Have you tried this? https://www.amazon.com/The-Economist-US-Edition/dp/B0027VSU9S
Just like clicking "Get the free Kindle app"? Maybe that'll do it for you. I'm not sure about a regular Kindle.