Someone else is selling your ebook on Amazon? Here's what to do...
Occasionally, pirates will attempt to re-package and sell your work on Amazon. They might even take a free ebook that you have written and try to sell it for money.
Obviously, this is a violation of copyright. Amazon will not detect those violations on their own, so you need to tell them.
Simply go to Amazons "Report Infringement" page: https://www.amazon.com/report/infringement
Fill out the form. This will get the pirated works taken down fairly quickly.
For more information, read this article where author Rob Bignell shares his experience with piracy on Amazon.