It is important to note that bookstores have the right to send back copies of your book. (katemcolby.com)
If not, the bookstore can send back the copies they didn't sell for credit. (courtneymilan.com)
After contacting it, you'll need to fill in and post back a copy of its complaint form to explain your case and so that it has a copy of your signature. (moneysavingexpert.com)