Como resolver problema de facturación en compra anterior?

If you are getting a 'problem with a previous purchase' message then that implies that iTunes wasn't able to collect the money for your last purchase, you will have to add a payment method to your account that's accepted by the iTunes validation, or if iTunes gift cards are available in your country you might be able to redeem them onto your account and use them to pay what you owe. Until that is paid you won't be able to download anything else from the store, including redownloading items and updates to apps.