As part of the dunning flow, you can determine how many times we reattempt a customers payment once it's failed or declined. You can also determine what you want we should do with the customer and their subscription after the final attempt. It's important to note that once a customer has been cancelled, you won't be able to reactivate their account. This means that if you want to add another subscription to this customer, you'll need to create a whole new account, which means collecting payment details again. To avoid churn, you might want to avoid this.

If you want to avoid any of your customers getting cancelled after a failed payment, you can amend your dunning settings. To do this, navigate to Settings > Configuration > Dunning and Failed Payments > Declined (tab)

Here you can determine how many times we reattempt a payment and after how many hours. You'll also need to choose the status of the customer on failure of each attempt. If you want to make sure that the customer account stays active, you'll need to specify this here.

You'll also need to make sure you also change the Writing-off the invoice section in bottom right corner.

If the invoice is set to write-off immediately, or scheduled write-off, you'll need to make sure the subscription status is also set to Active here or the customer could be cancelled in this final step.