Cell C systems not working for stakeholders

I am completely unhappy with Cell C and all their call centre agents. My contract expired in December 2021 and I did not call to cancel it. Cell C continued to debit my account and when I called to cancel it (as they claim i should cancel it from my side), I was transferred to the cancellations section and after holding for about 30 minutes the call cut. This has been happening since then. Today they called me stating that I was on arrears, after stating that I wanted to cancel the contract they put me through to the cancellations section. When they finally took the call they conducted a security check and then told me that I answered the questions incorrectly and would therefore need to go to a branch or call again some other time. Meanwhile Cell C continues to debit my account, also stating that I am on arrears. I want to make it clear that I will not be paying up any amount towards the contract and Cell C can pull their records to find out how many times i have tried to call them to try and cancel the contract to no avail due to their dysfunctional phone system, including the security checks system.