Sent me a book without my authorization

Better Homes and Gardens have sent me for a second time a Gardening Made Easy book without my authorization.  My account number #10023406746 as shown on the invoice they sent with the book.  I have already filled out a fraud complaint with the USPS, called their phone number on the web site for BH&G and was unable to talk to a representative. I refuse to pay the $31.31 for the book or $5.95 to ship it back. . What more can I do to get them to stop???????