Billing errors -missing data -poor assistance

This is my final straw with mtn. They have the worst customer service, I received my Jan bill for a data contract that says I have exceeded my bundle and incurred charges on a day I never used my device. Bunch if *******, they never help you to cancel a contract, there franchise stores don't comply with cpa as they don't allow client to enforce his cooling off periods. I have been over charged about 5000 rand on another contract. Possibly the worst service provider. No one ever phones or emails you an update in respect of the investigation, if you lucky you are sent an automated response! And there call Centre staff always provide the incorrect information. Why can't you speak to someone dealing with accounts directly???? I asked for the cancelation amount for my contract and I was told that the consultant does not know! MTN wake up you gonna lose all your customers as a consequence of your non existent service and dishonest ********* practices.