Sent when a payment is recorded as completed. A card, cash or other payment taken at checkout completes immediately; a bank debit completes only once it settles, which can be several days after checkout. A bank debit that has been submitted but has not yet settled does not send this event.
410Endpoint gone. Subscription auto-deactivated (EndpointGone); delivery abandoned. No retry.
415Unsupported content type. Subscription auto-deactivated (EndpointUnsupported); delivery abandoned. No retry.
429Rate limit exceeded. Delivery retried after Retry-After delay (default 60s).
2XXWebhook received successfully. Delivery marked Delivered.
4XXClient error. Delivery abandoned; subscription stays active. No retry.
5XXServer error. Delivery retried with exponential backoff up to maxAttempts.

