call 800-310-6261, ignore all the mumbo jumbo and press O to get directly to an operator. They will cancel, no questions or arguments.
Send them a written letter and included your name, address and RD account number. Better still, send them a mailing label along with your written request.
Newsstands, bookstores or if you are overseas, visit the web link below.
you can't if you dont want it anymore just dont go on it
Wiki is a separate web site from Yahoo and does not have access to that information. See the link below for possible reasons listed by the Yahoo site.