According to the terms and conditions, people that cancel without using any Prime benefits (such as free shipping or Prime Video) could also be automatically eligible for a refund.

However, consistent with DoNotPay, you'll request a partial refund for the remaining time. It seems to be hit or miss on whether or not you will get one, but it's worth contacting Amazon support and asking.

I contacted Amazon's chat support while researching this text and was quickly told that there have been no refunds given, but you'll have better luck than I did, especially if you're fully closing out your account. DoNotPay recommends calling Amazon support or using the Contact Us form rather than chat.

Below we'll show you ways to cancel your Prime subscription, request a refund and shut out your account. it is not necessary to shut your account if you're only curious about unsubscribing from Amazon Prime. We'll also sum up the Amazon services you'll not be ready to use.
How to cancel your Amazon Prime subscription, check in to your Amazon account and click on the Account drop-down. Then, select Prime Membership. Next, click Update, cancel and more under the Membership heading, followed by End membership. Alternatively, you'll visit this support page and click on the top Membership button to leap straight to the proper page. Visit - Amazon.co.uk/mytv

You'll have to verify three different times you would like to cancel your membership. Amazon will plan to move you to at least one of several other options (also pictured below):

A monthly rather than yearly subscription Receive an alert a couple of days before your subscription renews so you'll decide then If you would like to cancel your membership completely, you will need to maneuver past these other options to urge thereto point.