What happens now if you try to sign into that account? Anything?
You called the right number for Comcast security. They should be able to reactivate the ID for you. When a user ID (that part of the email address to the left of the @ symbol) is changed or deleted, it is suspended for 90 days, and then released back into the pool of available IDs for any Comcast customer that wants to claim it. During the 90 day period, the account is actually still active-----you just can't get at it. If I were to send you an email at that address it would show up in that Inbox folder. You need to call back and keep after them. If you still can't get it done post back in here and I will escalate the thread for follow-up.