How to change my icloud mail account name

I have set up icloud e-mail no problems however when I have checked the settings after the initial save in

settings>icloud>account>Advanced my email address shows stephen.rading@me.com it shoukld be stephen.reading@me.com I am missing the 'e' on the surname. How can I modify this so as to add the 'e' I have deleted the account and reset up but it keeps defaulting to the minu 'e' address?

any assistance very much appreciated