I was downloading ios 7.0.3 and there's the new thing keychain and I putted the wrong number... How can I change it?
Go to Settings>iCloud>Account>Keychain (at the bottom), tap the number shown then enter the correct number.
That is not working, because you don't get the first security code and then you are stuck. I mistyped my number and send it by mistake and now there seems to be no way to change it. I can't see the number in the settings.
See if this helps: http://support.apple.com/kb/HT5834.
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