how do you change a sub account into a master account

how do you change a sub account into a master account?
i think my account is a sub account and it wont let me change my billing info to buy the new cod 5 maps. How do i make it a master account so i can change my billing info?
PlayStation - 3 Answers

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1
you have to pay for a master account i think.


2
Sorry but I don't think you can! Sony needs to be very cautious about people sueing them for cyber bullying etc...


3
You can manage your account status and credit card information at the official PSN site: https://store.playstation.com/login.gvm