FINALLY FIXED THE ISSUE!!
After a month of battling with chat and phone support I believe I was able to fix it myself, though the last two people I talked to said their was a programming glitch on my account which wasn't allowing them to close an open work order, and I wouldn't receive a Security PIN until it was closed.
Not sure if they closed it or not, but when I logged in today I saw the same FCC message that you are all receiving.
I went to this page: https://customer.comcast.com/Secure/Users.aspx and the update button worked directly from there. I clicked resend PIN and it showed up in my Comcast Email immediately. I updated it and changed it to something I can remember. Now everything is working fine.
Good luck!
