Debt collection

I have been helped by many agents telling me that they have updated xyz when it came to a bill that I got after canceling the service and returning the equipment and I have been trying to get that bill resolved for awhile now. When I cancelled the agent told me I would not get charged an early termination fee which is what caused my whole confusion as to why am I being billed this amount? When contacting support, agents would tell me it would get readjusted or that they could take off the early termination fee but I never saw the bill change. An agent even told me I would get a refund?? Im not sure what they meant by that but nonetheless it stayed the same and finally, I called once again to see what is happening and why the bill stayed how it is and why am I being told different things because now my account has been sent to debt collection. I even asked an agent if it was possible they can add a note or something on my account letting Xfinity know I was trying to resolve this bill. The last agent I spoke to explained to me in detail what I was being billed with and why an early termination fee couldn’t be taken off. If an agent would’ve told me this since the very beginning, I would’ve paid my last bill already. I told the agent that I will pay the bill then knowing the bill can’t be changed or readjusted as how I was told before, and the agent said doing so will take my account off the debt collection agency. But I have seen many posts saying that they’ve been told the same and it ends up staying in their credit and it doesn’t get taken off. So I’m taking initiative written action so I have proof. I would like to know how I can send a direct message to Xfinity support to have written proof that the account gets taken off of debt collection. Xfinity, you should really tell your agents to not tell customers they can do or will do something and end up doing nothing because us customers always end up paying with worse problems afterwards…