8ta denyimg me what is rightfully mine

I have been fighting with 8ta since November last year, about a mistake that they had made. I am now in a predicament where the said device, contracted by them was ****** and when requesting to block my cellphone in order to obtain a ITC number for insurance purposes they said that they are unable to assist me as the number is inactive.It had then been brought to my attention that 8TA did not upgrade me , but they added a new contract in my name, adding to this the consultant who assisted me with the upgrade was a trainee. All this became evidemt, when enquiring about the amount due for the period December. I have been on the phone with call centres, been to the stores but nothing has since changed. My bill is now close to R 1500 since then, and they cannot give account for this as they have different answers all the time. There customer service is pathetic aswell as there response time. I am still waiting for information as I need to finalise the processing iof my claim,. also I have refused to pay anything to 8ta until they have resolved my issue of ofcourse I still have not heard from them. Please help as I have now had enough, and I'm done being NICE!