There can be a few reasons why your Revolut card isn't working on Amazon UK:
-First, make sure that you have entered the correct card number, expiry date, and CVC code.
-If your card is still not working, it's possible that Amazon UK has flagged your card for security reasons. In this case, you'll need to contact Revolut's support team to get help.
-It's also possible that your card has been blocked by Revolut. This can happen if you've reached your monthly spending limit, if you've been making too many transactions in a short period of time, or if you've been using your card in a country that's not supported by Revolut.
If you're still having trouble, you can contact Revolut's support team for help.