Once the transaction has been cleared, you can refund the full amount (full refund) or part of the amount (partial refund) to your customer's card, as long as there is an available balance on your viva.com account:
Log in to your viva.com | Account
Choose "Sales" and then "Transactions".
Find the transaction, click "Refund'' and enter the amount you want to be refunded.
The time it takes for your customer to receive the refunded amount varies, as it depends entirely on the issuer and the type of card.
The charges resulting from each chargeback are detailed in the viva.com Price List.