Good morning :) My name is*****'d be happy to assist you with this. iTunes/Appstore requires that you have a valid payment method on file in order to be able to purchase apps, even free apps. Since you can't use that closed account, you'll need to go to https://appleid.apple.com. Please login with your apple id and password ***** you can manage your Apple account to update billing information (add a new payment method), update your email address and/or security questions, etc. Once you have done that you should be able to purchase new apps and make in app purchases with existing apps.
If you need help with your Apple Id or password, please let me know.
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