Depending on the type of payment method you use, refund may typically take up to 14 days to process. This is because the banks do not usually finalize a refund immediately and the authorization hold of the funds may take up to 14 days to expire.
By default, all transactions will be refunded to Store Credit. However in the event that the cancellation reason is due to the payment not passing the verification, then it will be refunded back to the account of the payment method which you originally used.