Help Topic
Goodreads on Kindle says My Account is already linked
Currently, Goodreads on Kindle only allows you to link your Goodreads account to a single Amazon account, and vice versa. If you try to sign in to Goodreads on a Kindle with a different Amazon registration, you'll see an error message that your Goodreads account is already linked to an Amazon account.
If you see this message on your own Kindle, it's possible there's a problem with the link between your Accounts.
In either case, the easiest way to fix this is to visit the Apps Tab and unlink your Amazon account, then try to sign in on your Kindle again. You should be prompted with a fresh sign-in page, and should no longer see the error message.