What happens an auto-charging payment fails?

When it comes to failed payments, it is best to turn on the option to send customers an email for each failed payment with instructions on how to update their payment method. You can turn this on in Seal Subscriptions > Settings > Notifications.
Overall, the app will retry the payment as configured in your Seal Subscriptions app > Settings > General Settings > Billing settings. If the payment fails on all tries, then the subscription will be cancelled automatically.