MTN won't let me cancel my contract

My contract was set to expire in May. I've been trying to contact MTN since January to enquire about my account however have been unable to. As per the original agreement I assumed last payment would be end of June. In June I was contacted by the call centre and they tried to persuade me to renew my contract which I declined. They told me if I didn't cancel it I would still be billed monthly. When I asked if he could help me he said he could not even see when my last payment date was or any other account info nor could I be transferred. I was told I had to go to a branch to cancel the contract. When I went in to MTN I was told by a very rude sales person that I had to call MTN as the branch does not handle cancellations. I had to call in to the retention department. I called 808, was given a whole lot of bullsh*t options that weren't what I needed. I chose the option to speak to an agent and waited on hold for 1 and a half hours before I hung up! I'm DONE with MTN and their sh*t. I had issues when taking the contract and issues now when trying to leave. MTN needs more competent staff then maybe they'll get their sh*t together. And I still haven't been able to cancel my contract!!!!