Amazon Appstore Temporary Login Error FIX!
If you flash your phone a lot, chances are you will eventually run into this problem of logging into Amazon Appstore.
If you are having this problem click this link and deregister some of your devices.
It's got a soft-limit of around 20 or so. Deregister some of the replicated devices in the list and the problem will be fixed.
Hope this helps someone, worked for me!