I don't have an Xbox, but same problem. Channel lineup wrong on my computer. I call and is connected with people who can't get a grip to what I'm saying. So I go to Chat..same thing. I asked what state was he in...India!!
if you have rebooted the desk/laptop and the time is set righton the PC call 800-Comcast and select billing and ask the agent to verify that your account location is accurate and ask for a deep account background database refresh to be peformed. otherwise an official Comcast employee will usually reply within 72 hours of your original post.