Why does my Ipad keep telling me that my security code is incorrect when i am trying to update the billing information?
It might be because the billing address you provided doesn't exactly match your bank records. It has to match your statement exactly. See http://support.apple.com/kb/TS1646.
I've ran into that a few times. Always on my iPad. I just updated it on iTunes on the computer. The iPad can be finicky sometimes with updating information. My work around, if it was doing that, was updating on computer.
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