Cell C pathetic

Please can anyone assist me and tell me who to phone in order to sort my problem out with Cell C. I have been trying since Oct 2018 to fully resolve this case. They activated a new line for me instead of upgrading my account and took a extra debit order which I never agreed to since end off Oct from my account, total amount until today R725.46 was taken from my account. Eventually I was told that the extra line has been cancelled and that I will be refunded. I received a sms on 8/2/19 saying that the money will be in my account 3-7 days, today I phone again Cell C to get a update because no money has been paid into my account, the lady told me she does not understand why the R400!!!!!!! was not paid into my account yet, the amount due is R725.46!!!!!!!. a New case has now again been created!! I want to speak to a director or manager that can resolve this please. I am fed up with call centre agents phoning me and not resolving the case. Everytime when i complain they comment that a agent has been in contact with me and the case has been resolved..this case has not been resolved!!! I still did not get any refund and the amount is wrong!!!