Bottom Line Books repeatedly billed me for a book I returned Des Moines, Iowa

I ordered a book on approval.  It didn't meet my expoectations so I choose to return it. I sent a letter to the company requesting a postage free mailing label so I could return the book. They sent the label which I attached & took to the post office.

For the next 2 months they sent increasingly threatening letters requesting payment " before the account goes delinquent"

I finally researched their phone number ( never provided ) , spoke to a customer service rep. who said although they never received it ( she claimed ), they'd remove the charge & close my account.  We'll see next month.