comcast comcast/xfinity phantom billing seaTTLE Nationwide

I paid my internet/cable bill in full (double play) of $139.91.  I received a text the next day saying thank you for your partial payment of $57.00.  I checked with my bank, and the $139.91 had been withdrawn and paid to Comcast.  I then checked the Comcast website, to see if the text was in error.  No, they still want 87.91 to be paid, after receiving 'partial payment'  I called Comcast, spoke to a rep and a supervisior, who spoke english as a second language, and were hard if not impossible to understand completley.  They say? I think that when I ordered double play, I had a bill and my payment was creditied toward that.  I paid a $100. equipment deposit when I ordered the double play.  No where on the current or past bills, does it show a past due amount, and there is no tracking showing that the $87. was paid toward something else,  it is reflected no where on the on line billing.  They can not just take part of a payment, and send it off to lala land, and not show it was paid.

When I first moved back to Seattle, a year ago, after living in Dever for four years, and having an account in good standing in Denver, they made me pay bills for my address in Seattle for other people who had lived at the address and not pay the bill, plus a huge deposit.