Changing Apple ID from Phone Number to Email address

I wrongly setup Apple ID as phone number. How do i change it to Email address.

I went with below option , it didnt work out. can some one suggest please

1. Go to appleid.apple.com and sign in.
2. In the Account section, choose Edit.
3. Choose Change Apple ID.
4. Enter the email address that you want to use.
5. Choose Continue.