Vodacom contract mess (********** account issues)

I am just about to lose it with Vodacom. I had a contract with them which expired in November last year. We subsequently discovered that there was a ********** activity on my account where someone tried to renew the contract by ordering an Iphone. I actually then remembered their field workers had visited our office park and i was interested in their fiber offer, my assumption is that they may have used my vodacom number from that point when i filled in the form, but i can't confirm this theory, therefore i dont know how the ***** happened. Based on this incident i decided i wanted to cancel my contract when it comes to an end and i no longer want to proceed with Vodacom. I called them and told them i do not want to renew my contract, because of the incident, then they said they will open a case and investigate and they cant close the account until the case has been resolved with their ***** department (Whatever that actually means) because despite the numerous time i spoke to their consultants, every time a new consultant calls me they do not have information about my case in front of them. I just spoke to a consultant and told then to find all the information about my account which is now sitting at R1507.60. and he said he will check, five minutes later i receive an sms stating that i qualify for a reduced balance of 1280.31 what crazy tactics are these, i didn't realise that we were negotiating. I am worried that this will affect my credit score as i am currently looking for a wifi supplier at home.