MTN & MTN Insurance

I have a contract with MTN now for about 6 years. When I initially took the contract out they asked me about insurance and I agreed to take their insurance as I did not have any of my own. Last year November I notice an increase in my monthly bill and left it as I was not sure what it was about. Last month I phoned MTN and asked why I have been getting sms's that a Miss Nonjabulo was added onto my insurance with MTN??? This was in December 2017.

On the 27th of March I cancelled my insurance and queried all the amounts now going off my account since then as now in March I am paying for 3 devices and I only have 1 on contract?????

Since the 27th of March I have been phoning MTN asking for my credits that had to be passed and everytime I get a reference number but up to now nothing has been sorted as I just got a new statement informing me I owe them R2000?

They are aware of the situation and do not want to rectify it on their side but they are quick to phone and ask why the account was not paid? Which a matter a fact happened and I explained it to the lady over the phone?????

I really dont know what to do anymore as I am getting no joy from them.