We were able to remove the other identity the customer had created which only had their email and the correct username, then send an invite via to their current account to verify the address, and they were able to modify their username in My Account and set up Two Step Verification. If you're also experiencing this issue, please post your own thread. The best thing to do is to invite the email you'd like to use in question, and remove it and add it to your current identity. Reminder: Your Xfinity ID is your email and mobile number, usernames are legacy and can still be used, but the quickest way to get into your account are the first two options if they are both verified on your identity.
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