post https://core-h.mkbank.com.br/api/pix/refund
The Refund a Pix Cash In endpoint allows you to initiate a refund for a previous Pix cash in transaction. You need to provide the end_to_end_id of the cash in transaction that you want to refund and the amount to be refunded. The amount must be equal to or lower than the received amount of the original transaction. Optionally, you can include a correlation_id to associate the refund with a specific identifier.