cancel membership

Ladies and/or Gentlemen good morning,
I kindly ask you to cancel my membership because in spite that i have sent several messages asking to change my email (as a matter of a fact it is already changed for my login), Techrepublic continue sending all messages, news, etc., to my previous email address.
It has been not possible you stop sending emails to my previous address!!!
So i am forced to cancel my memebership in order to stop it!!!
Best Regards:
Jose Y. Solano