Why is the invoice collection still being attempted when the subscription is canceled/terminated?

Dunning is a process that directly follows the invoices issued to an account and does not look to the subscription or subscription status to stop. This means, if a subscription is canceled or terminated and there are past due or open invoices on the account canceling or terminating the subscription will not automatically stop the collection attempts on these invoices. You will need to also go into each invoice and under the invoice actions dropdown menu use the stop collection option to fail the invoice. This will permanently stop the collection attempts against any past due/open invoices on the account if no further collection attempts should be made. Currently, this is not done automatically when a subscription is canceled or terminated.