Ignored Tickets

I have been dealing with this problem coming up on a year now. I was wrongfully charged for 3 months of internet after I returned my modem and hardware back to the Xfinity store. I did not pay this amount because I no longer lived there nor used the internet (I had to provide proof of my lease ending at that location to the reps that I was explaining this issue to, and would be able to provide this documentation if needed). I brought this up to the chat representatives and they understood and gave me a ticket for that money to be either, refunded or for that amount removed from my account.  Ticket ID: [Edited: "Personal Information"], which was said to be generated by a supervisor because of the hoops I had to jump through just to get a ticket. That was about a year ago. I thought this was solved until I got a notice that I still had an outstanding balance over the same issue(I have no used this account for any Xfinity service since). I have been on the phone with the low level support reps that don't seem to have much control over this type of issue, as I have been passed back and forth between departments with no real solution. I finally received a ticket from a nice rep that seemed to understand my problem. Ticket ID: [Edited: "Personal Information"]. I received an update on this ticket this morning saying that it was closed (I still have a remaining balance). I'm quite frustrated that this has been a revolving issue for this long. I have all transcripts from every conversation that I have had with reps since last year and would be willing to provide that to you if a rep here is not able to view that.