Yes, as soon as you select that you sold the car (under 3rd party) on tesla . com, the car can no longer Super Charge. The new owner needs to log into their account and add the car. They will need documents. I purchase a car from private sale and was stuck trying to get home without SC. I was able to add the car to my account by using the bill of sale. Usually that's not the case. They also let me get in one SC event until it was added to the account. It sure is much better than how it use to be. It would take weeks before the car was removed from the app or someone had access under their app. Now, back to your CC. Are you able to remove your card from your account now that the car is off your account? I think all should be well now that the sold Tesla is no longer on the account.
Let us know.