How to cancel the subscription from Amazon Store?

To turn off auto-renew of Amazon in-app purchase, please do the following:

1. Go to your Amazon account - https://www.amazon.com/your-account
2. Select Your Apps under Digital content and devices.
3. Select Your Subscriptions under Manage.
4. Update your subscription as needed.
   Note: If you turn off auto-renewal for a subscription, access continues until your current subscription period expires.

Here is the instruction - https://www.amazon.com/gp/help/customer/display.html?nodeId=GDT2SXJJ7K49JKYE