In order to put or check the guest Credit Card details open the reservation window and go to Reservation Details tab or Guest Details tab. There you will find a button Show Credit Card Details:
FrontDesk Master receives credit card details from portals:
The credit card details are kept in the system until two weeks after the reservation's check-out date; after that, they are removed from the system.
In case the CVC is missing in FDM, you may retrieve the information by contacting your Account Manager (or Customer Service Team).