Q: I need to fix a billing problem.

I need to fix a billing problem based after I wasn't notified of any charges to my account from a purchase and when the money was set to be taken out there wasn't enough money in the account. But now I have enough money in the account and I'm not being charged, I even bought an iTunes gift card to even out the problems which worked last time but now it's not equaling out and taking the money from the 15 that's linked to the account now. Please help me to fix my problem.