From the FDIC website:
It's easy to change your mind about a purchase or not realize that you have signed up for a service that will result in monthly charges. And while many merchants offer easy refunds or exchanges, sometimes you may need to stop or withhold payment. Here are several key facts to know when you want to stop a credit card, debit card, check or pre-arranged payment. Read more
The process to stop an automatic recurring payment made from your credit card differs from that of stopping one made from your checking account. In both instances, however, the important thing to remember is: document, document, document.