There is no reason to give your social security number. They may choose to validate it is you by the last 4 digits of your SSN, but you can request an alternate way. Now, the secret is call them back again. Each new call routes to a different area. Keep doing this until you get some one that can help you. I know it's a pain, but them again so is Comcast.
Comcast is the absolute worst I think I talk to them almost every day because of a problem they add things to your bill that you don't ask for so you have to check your bill carefully as for canceling I've never had a problem when I wanted to cancel something I would suggest you talk to his supervisor if you haven't tried that or speak with the Better Business Bureau good luck
This is a google forum about the Comcast building- you've got a problem that may require legal advice. Best to contact an attorney, Legal Services, or go to a legal advice website. Good luck!
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