I bought some apps on iPhone and didn't have enough money what should I do?

So I have a prepaid debit card with 25$ loaded. I already bought something worth 20$ I then bought an app that costed.99 and another for 2.99. I went to check on the credit card site and it said the item I bought for 20$ is complete and it shows 2 item for.99 cent pending. It dosent show any app for 2.99 like I bought it for. Now apple won't let me update my app saying my card is decline. Can I buy a new card so they will charge the new one or will they still charge the old card and I'll have to pay stupid overdraft fees?

If it's one of the pre loaded gift credit cards you shouldn't have to do anything, just throw it away, I went over 40 dollars one time, and I called them and they said you could mail in a money order to the company, but I didn't do it and that was over a year ago and nothing happened still.