Upgrade without my auth and not sorting it out

I have a contract that was due for an upgrade in May15.Which I never did.Then in Oct I saw that my debit order was increased and when I switched the tablet on I saw that there was sms that came through saying that my contract was upgraded. I never upgraded my contract and never gave anyone auth to do so.Then I went to an MTN at the Grove where the consultant said that the contract has been upgraded and that I am not the first person to complain about the same story.they think that the call centre upgraded my contract without my knowledge and it cant be that someone took my id to do so because there is no handset allocated to this contract.it was just upgraded.They could not help me and said I need to go to a Service centre,Which I did and they just did not want to help me.Then I called the call centre Mon 9/11/15.I spoke to the guy and said I wanted to speak to a manager,he explaind the situation to the manager(Chad) which then spoke to me and said that he will sort this out.Go through the notes since the upgrade and it will be sorted within1-6 days. ***.Today I phoned and they said nothing has been done.Now I will go and open a case of ***** at SAPS against MTN.USELESS!!