I've moved your question to Customer Service. You can also call 1800comcast.
I've asked a Comcast employee to help you. You should expect a reply in this thread.
Hi, 1234solis - I can help with your request to upgrade your services. Please send me a private message with your full name, the account holder's name and address as it listed on the billing statement, a phone or an account number. Also, please include the changes you would like to make.