409 Conflict - Session Expired

Indicates checkout session has reached it's expiration point. Initiate a new checkout.

{
  "type": "https://developer.sumup.com/docs/problem/session-expired/",
  "title": "Conflict",
  "status": 409,
  "detail": "The checkout session ae98b9cc-2287-4621-afa1-d36ae2ea219d is already processed",
  "instance": "1bfe72b34387"
}