This can be done under Profile and settings:
- Login to your PayPal Account.
- Click on "Profile and settings".
- Click on "My Money".
- Look for: "My Preapproved Payments".
- You should see: "Manage the automatic payments, subscriptions, and installment plan payments I send to merchants".
- Click on "Update".
- Next, you will see all active and cancelled billing agreements/subscriptions listed on the screen.
- Click on the service-name for further action.
- You should see on next page terms of billing agreement/subscription, how much money you have authorized service provider to deduct from your account and few other details. Most important is link to Cancel agreement, in case if it is active.
- Note, when you click on Cancel, you will be prompted to confirm it once again. Click "Yes".
As a last option, if you're stuck - suggest that you contact customer support - they can walk you through the steps. You can contact them via email, phone or through Twitter @AskPayPal or via Private Message on their Facebook page at https://www.facebook.com/PayPal
