Create function in oscommerce to release reserved tickets on ticketing website

On a website where tickets are ordered, a system must be added to clear the tickets that are reserved, but never paid and sent to the customer. That way, the reserved tickets can be sold again. You can add a button in the admin in the serial number section to clear them. Tickets the serialnumbers of the tickets can be found in the tabel: product_serialno If there is an "order_id" and "confirmed" = zero and "date_purchase" is zero and "date_ordered" is older than 30 days Than clear the "order_id" and the "date_ordered".