Q: My giftcard value shows on my new iphone but I can't spend it?  How can I change this?  Thanks.

What do you mean "can't spend it"? What happens when you try to make a purchase?

Again, what exactly happens when you try to make a purchase? Just saying "can't" and "won't let me" doesn't give us anything on which to base a diagnosis and offer suggestions.

If it's asking you to verify your billing information, just do that. It's a security precaution that pops up from time to time. Once you verify the billing information, the purchase should then be applied against your credit balance from your iTunes card.

If you continue to have problems verifying your billing information, or after doing so your credit card is charged rather than your balance, go here:

http://www.apple.com/support/itunes/contact/

and follow the instructions to report the issue to the iTunes Store.

Regards.

You're quite welcome. Cheers.