You can cancel anytime from your device settings: Apple → Settings → Apple ID → Subscriptions. Google → Play Store → Subscriptions. Web → contact us by email.
Go to My Account and tap "Delete my account" at the bottom of the page. Your email and name will be permanently removed.
Go to My Account and tap "Change" next to your email. We'll send a verification link to your new address.
Try closing and reopening the app. If the issue persists, contact us by email with your account email.