In addition to creating you Amazon developer account, you'll need to make sure that the necessary payment and tax information has been filled out to complete the set up of your Amazon Developer account. Follow these simple steps to make sure your payment information is complete.
1. Login to your Amazon Developer Account here
2. Click on Settings.
3. Click on Tax Identity and fill out the Royalty Tax Identity Interview
For direct instructions from Amazon navigate here: https://developer.amazon.com/docs/reports-promo/setup-tax.html