We have developed our APP to connect with Alexa. It can work before. But since last month, we cannot login with Amazon account. It responded as an occur error.
In order to investigate this issue further we will need specific information about which app in your account is causing this problem. To protect the personal information of developers, we do not discuss the details of specific applications on these discussion forums.
Please reach out to us via our Contact Us form (https://developer.amazon.com/help/contactus.html ). This will allow us to validate your identity and discuss app specific information in a context that will not expose your personal and proprietary information.