Login to your account at https://www.bluecoffeebox.com/customer/account and click the "Edit" button under Your Subscription(s).
On the next page, you will see a "Cancel Subscription" button at the bottom.
Please note that cancelling a subscription simply stops the next future renewal payment. It does not stop pre-paid subscriptions and does not automatically refund monies.
If you cancel, you will still receive all pre-paid coffee deliveries.