Could not stop billing even after disconnected!

I switched providers back in January of this year, and took the necessary steps to disconnect my Comcast. I called their customer service to cancel the service and was informed that I would need to take in my box to a nearby location. The CS rep gave me an address, which turned out to no longer have a Comcast office there. My wife manages an apartment community and therefore saw a Comcast rep nearly every week. So, we simply gave him the boxes and he wrote us a receipt. At that point we were completely paid up on our account and had obviously satisfied our portion of the deal.

I figured that was the end....

But we began receiving a new bill each month afterward as if we had never canceled the service at all. I called customer service and waited on the line 15-30 minutes each time to be told by each representative that they had, "Taken care of the issue and credited my account back so there would be no further charges." I, being a kind and apparently gullible person, believed them. But, to my dismay each month we would receive another bill with an ever growing total amount due. They even sent someone out to my house while I was at work to hang a "You will be disconnected!" sign on my door!!! I DIDN'T EVEN HAVE SERVICE! At that point I had been on another provider for over 3 months!

After 4 months of this non-sense I finally spoke to an intelligent rep over the phone who told me that looking at my past call history showed nothing more than reps leaving comments such as, "Customer called to get his bill status."! He said he could put in another request to have my account credited back to $0.00, but that the only way to be completely sure it was done would be to physically go to my local Comcast Pay Center and have them print my receipt of cancellation and full credit.

So, I took off work early one evening and went well out of my way to the Pay Center. I politely described the problem to the girl behind the desk and told her that I REALLY needed to get this resolved before my credit began to suffer due to Comcast's apparent inability to disconnect my service and terminate my billing. She credited my account down as far as she possibly could and informed me that there was about $102 that she would have to have someone else remove and that there was about $25 that accumulated between the time I was disconnected and the time I turned in my box, which again, was not my fault due to the Comcast drop off location vanishing. Plus, I was told by the first rep that the charges that accumulated for not dropping off a box would be waived if the box was returned promptly.

So, I went ahead and paid the remaining $25 and listened to the girl promise me that I would never hear a peep from Comcast again.

But, alas, the following month I received a letter from the collection agency. Wonderful....

So, again I left work early to go back to the Comcast Pay Center and argue my case. The girl initially told me she would have to again submit for the $102 remaining balance to be removed. But, after nearly 6 months of being jerked around I demanded that she contact whomever necessary to remove the $102 at that time. She called and waited on the line and finally got ahold of someone who removed the remaining balance. She told me that I would need to call the collection agency to have them contact Comcast....someone named Karen....and have her verify that the bill was removed. Karen is apparently the collection agency's contact at Comcast.

So, I called the collection agency only to find out the method she had explained does not work. Apparently I need to send an official letter to the collection agency with all of my "evidence" and it could take up to 30 days or more to resolve. And even then, there is no guarantee that the mark on my credit will disappear, it will probably show "is paid".

I need someone who can actually make something happen to contact me or better yet, contact the collection agency and get the notch on my credit REMOVED COMPLETELY.