In which state is Comcast corporate headquarters located?

In which state is Comcast corporate headquarters located?
PennsylvaniaComcast Corporate Headquarters
1500 Market Street
Philadelphia, PA 19102-2148
I'm in Seattle and in July I paid my comcast bill early on line. My bank sent the money to them they sent it back to my bank. Then they charged me with a returned check charge and a late charge. I got a notice two weeks after I paid it. So I called and talk to a person and a supervisor. I was told to go ahead and pay the charges and they would credit it on my next bill. I paid the org. bill and I told them that I would pay the charges because I didn't owe it. My next bill came and the charges were still on it I paid the bill and not the extra charges. They called me and I talked to them they said ok. About 2 hours later I get another call from them about it and they looked it up and said ok I see the notes about this but you still need to pay this. The next day I get another call this time I was getting a bit pissed about the whole thing I asked them so what you are telling me is that because you made a mistake on my bill and you know that and I refuse to pay what I don't know you are going to shut off my cable and they said YES. Today a week later I have gotten a shut off notice.
Chuck from Seattle