My mom got me a $15 iTunes card a couple days ago. When I got it, I tried to make a new iTunes account since my dad and I have (accidentally) the same one and I didn't want him to accidentally use the gift card.

So, I entered in all the information till it got to payment method. I put in the gift card code and entered it, then it said that my email was already in use (which it was a brand new email so I don't know about that too). So I entered a different email, then put in the gift card again, and every time I've tried to re-enter the code, it's said that it's been already redeemed! Any advice?