Cardiogram Premium is an in-app subscription billed through your phone’s app store account. Like other apps with in-app subscriptions and purchases; If you delete the app or deactivate your Cardiogram profile, you are still responsible for unsubscribing from premium to avoid being charged in the future.
Please follow these steps to ensure you are no longer subscribed.
iOS users: How to cancel a subscription from Apple.
Android Users: Cancel, pause, or change a subscription on Google Play.
If you subscribed to Cardiogram Premium by mistake and require a refund, you’ll need to submit the request through Apple or Google. Cardiogram cannot issue you a refund directly.
Follow these steps: https://support.apple.com/en-us/HT204084
Follow these steps:https://support.google.com/googleplay/answer/7205930