You can cancel your Premium subscription through your Paypal account.Once logged in to your Paypal account, follow these easy steps:
1. Go to Settings by clicking the gear icon at the top right corner of the page (besideLogout).
2. Click Payments tab
3. Click Manage Pre-approved Payments.
4. Look for the subscription related to your Comments Premium app and click it.
5. Look for the Cancel link and click it to cancel the pre-approved recurring payment.
6. Click Yes to confirm cancellation of Comments subscription recurring payment.