In the past, when I enter an Ultimate Game Card, I have CSC instantly. It's been about 15-20 minutes and they haven't been added to my account yet.

I tried to re-enter the card number and it told me it had already been used :/

Does it occasionally take some time to go through? Am I just being impatient?

If it isn't on your account in 24 hours, submit a ticket.

Thanks