If you want cancel subscription then Go to https://kiathemes.onfastspring.com/account enter same email which you used to subscribe. Then you will get email for Manage your Orders & Subscriptions.
You can Cancel Subscription from here by Clicking on Button Active Subscription.
If you want Remove your Saved Card , Then Click on Tab Account Details and Payment Methods.Click on Manage – Remove
Your Payment Methods & Cards info will be removed. & You will not get Billed Further.