post https://api-sandbox.y.uno/v1/payments//transactions//cancel
A payment with PENDING/AUTHORIZE status (due to card authorization) can be canceled before it is completed if payment is no longer required. This request cancels a payment with pending status.
If you request a receipt for the cancel transaction, once the one is created, you can do a get of the payment to find the receipt created in the "receipt_url" field in the payment.transaction object.
Note that this request requires an X-Idempotency-Key. Check the Authentication page for more information.