The most likely reason is that you unsubscribed the wrong email address. The email address we send each newsletter to is at the bottom of each newsletter so make sure you are unsubscribing that exact address. It is case sensitive as well, so enter it exactly as it appears at the bottom of the newsletter.
possibility is that a friend or associate is forwarding you our newsletter. If you continue to receive our newsletter after having successfully unsubscribed your email address, please forward it to us and we will investigate it for you.