I encountered this error on Firefox. It's correct on Chromium.
I'm writing OAuth client software with Authorization Code Grant for Amazon Dash Replenishment. I encounter error every time when I access URL like below. The serial is different every time. I access the URL after I deleted the device by "Manage Your Content and Devices" page.
The page says "Click 'Continue' to sign in to appname". So I click "Continue" button. And an error is shown.
> We're sorry!
> An error occurred when we tried to process your request. Rest assured, we're already working on the problem and expect to resolve it shortly.
I can go forward OAuth process from here when I copy URL of this error page and paste it to new tab.
For your information, I've never seen the error with Implicit Grant. But I can't use Implicit Grant because Implicit Grant doesn't have refresh_token.
I wish to use Login with Amazon with Amazon Dash Replenishment without error page. What should I do?