I cannot pay on App Store using my Apple ID money

I have 30 dollars that is held in my Apple ID account through using gift cards, I would like to purchase apps and other thing on app/itunes store using this money as that is the only way I will use it but it does not allow me and instead wants me to use a credit card. The option for it is there but I cannot click it and instead needs me to verify my dads credit card. I would like to know how I can fix this and use the money that I have.