One of the core eligibility requirements for Amazon Underground participation is that a non-Amazon Underground version of your Amazon Underground submission must be available for download from either the Google Play store or Apple App Store.
If you receive the above message on your “Review Status” tab, this means we were unable to locate your submission’s non-Amazon Underground version on Google Play or the Apple App Store.
Please provide the GooglePlay or Apple App Store link under the "Testing Instructions" section on this submission's "Binary File(s)" page. Once you have done this, please resubmit your app submission for consideration in the Amazon Underground program.
Please note that we do not evaluate your Amazon Underground submission to its free or paid version in the Amazon Appstore – you are welcome to maintain your current free or paid apps in the Amazon Appstore outside of the Amazon Underground program.
A general overview of Amazon Underground program requirements can be found here: Understanding Amazon Underground