I have seen this question posted a lot on the internet and so I thought I would post the answer here for everyone.
--Go to http://www.soe.com/ or you can google SOE (Sony Online Entertainment). --Click the button in the top right corner that says Login. --Enter your name and password (it's the same as for logging into the game). --After you do that it takes you to Account Management --Click the "Subscriptions Info" button --One of the items it shows you is your recurring billing. --In the box with your recurring billing information there is a button that says "Cancel." --Click it and make sure you read both buttons that pop up next, the "Yes" button appears on the right side at least some times so be sure you click "Yes" to cancel the subscription. --The update will be immediate, so when you go back to the "Subscription Info" button, it will show your remaining time and you will no longer be on recurring payments.
Hope this helps.
I'm desperately trying to figure out why kamikaze pilots wore helmets. Dave Edison