Reversal_flag values in AP_INVOICE_PAYMENTS_ALL

 Hi,

I would like to understand why does oracle populates the value 'N' in reversal_flag column of table AP_INVOICE_PAYMENTS_ALL when I pay the invoice by quick pay by navigating to Actions > Pay in Full on Invoice whereas the column value remains NULL if the invoice is paid through payment process manager, I do understand that it is marked 'Y' if payment is reversed but why does Oracle populates 'N' or 'Null' depending on how the payment was made, any help to understand the logic is appreciated.