You should save your card number for easy deposits in the future.
Once your card is saved you do not have to type in the whole number every time you want to make a deposit. You will only be required to enter the three-digit CVV code and the amount you wish to put into your Pinnacle account.
In addition, you will only be able to request credit card withdrawals to saved cards.
Therefore, save your card when you use it to deposit funds so you can withdraw your winnings back to your card.