I have $20 in my iTunes account but I failed many times to purchase $19.99 worth of platinum. I also tried the $9.99, failed as well. I've tried signing out from iTunes Store, Closing the apps, restarting my iphone4s, Signing in my iTunes account and trying to purchase plats. My in-app purchase is enabled and my phone is not jailbroken.
Help me please. Thank you so much!

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