Incorrect Caller ID

I have a landline with Comcast, but when I make a call to anyone who has not added my name to their contact list, the caller ID is incorrect.; In fact, the caller ID listed is my sister who passed away 10 years ago. The phone number was originally in her name -- she obtained it when she first got a phone for herself in the '70's. She did it through Pac Bell, which was then purchased by ATT. Then, I switched our service to Comcast.  I would very much like to correct this and have the caller id appear as my name. How can I do this?