Polling
ReadGET /v1/ramp/payments/{reference}?environment=sandbox and watch status.
Onstacks reconciles with the provider continuously, so polling every ten to thirty seconds is enough.
Webhooks
Register an endpoint under Developer or withPOST /v1/webhooks. Ramp payments emit ramp.payment.<status> events on every transition; see Webhook events for the names and Webhooks for delivery and signature verification.
What to show the user
Treatpending and processing as in progress. Mark an order done only on succeeded. On failed, show failure_reason and offer a fresh quote. On requires_action, show the instructions.