when you used the email setup to add your email, did it ask you for a username to create the account?
the email setup on the phone, should ask you the same information that going and doing it via the BIS page would.
if you have a problem, call your carrier about it and they should be able to either tell you your username, or reset it for you.
"That's it then. Cancel the kitchen scraps for lepers and orphans, no more merciful beheadings... and call off Christmas."