If Cancel a payment is executed for merchantPaymentId before payment, Cancel processing will be performed immediately after payment is completed and the status will be FAILED.
(If you want to disable "Create a code" immediately, use "Delete a code".)
1. Execute Create a Code.
2. Cancel a payment. (At this point, only reception is available and Cancel processing is not executed.)
3. When you make a payment on the app / screen, the status will be "COMPLETE" or "AUTHORIZED".
4. Cancel processing is executed and the status becomes "FAILED".
When executing Create a Code again, the merchantPaymentId cannot be used again; a new merchantPaymentId needs to be issued for the execution.