Dunning
What happens after a recurring card charge is declined: retries, reminders and, eventually, a cancelled subscription.
The word comes from the old English verb "to dun", to pester someone for money, but in the subscription business it is less about debt collection than about saving customers who don't know they are leaving. A large share of SaaS churn is involuntary. The card expired, was reissued after a fraud case or hit its limit. The customer wants to keep paying; the charge just bounces.
A dunning flow combines several tools. The decline code decides whether a retry is worth it, and retries are scheduled for days when payday has usually landed. Account updater fetches new card details from the issuer, while emails and texts ask the customer to update the card themselves. Hard declines, on the other hand, must not be hammered. The card networks charge for persistence.