Black Listed, Thanks to *********** Cell C

I have been trying to closed my Cell C contract I took out for my Mom after she past away over 7 years ago, I eventually gave the contract to my Dad. This Jan my Dad past away after a hard fight with Cancer, I have called and emailed since then to cancel my contract and when I was told it canceled, I canceled the debit order just find out that it wasn't and now I have been Black Listed with credit bureau for R195 and in all this time I have never received one statement from Cell C.... I paid this amount on the 2/07/2019 and when I ask to please get the letters of settlement and cancellation I was told to please wait till the 1 August now when I called to please ask for my statement and letters I was told to wait for the 7th August after fighting for 1 hour and 22 mins on the phone with Cell C, I still have not got my letters or Statement. How can I get this resolved when the part own needs to help me wont.