MTN No Call you back Centre

I have had a data contract with MTN for just short of 2 years and have never exceeded my 2 Gig allowance. I pay no more than R350 per month. For the month of July 2015 I received a bill for R1615. I contacted the call centre straight away to see why the cost was so high. I was informed that they could only supply me with an itemised bill to see when the data was used but not what what it was used on. Fair enough. Should be simple. I am now on my 5th call and over 2 hours of holdoing to the call centre after being promised that this will be resolved. I have even had promises from their supervisors that this issue will be resolved.In conclusion I am still waiting 3 weeks later and still no response. Once again proving that the big corporates are only interested in receiving your money and nothing else. MTN YOU ARE A DISGRACE. I have had contracts with you for over 15 years and this will be my last. I have threatened this before. I am sure you dont actually care as I am mearly a number.