Hassle to cancel Cell C contract

I have had a cell c contract for the past 6 years. My contract is coming to an end on the 13-04-2022 and I received an sms advising me to contact the call center should I wish to cancel if not they will continue to debit me. For almost a week I have tried to cancel online but no OTP comes through. I phoned the 084143 number only to be told by an agent called Nthabiseng that she can’t authenticate me and I need to go to the branch. Basically waste my petrol. I asked to speak to her senior of which she refused to give me her contact details including her full names because they are not allowed to give out their full names worse there’s no ref number I can use to follow up. I phoned the same department for cancellations to ask to speak to Mpilo who is Nthabiseng’s manager, only to be asked which Mpilo? I am utterly disgusted by cell c’s unprofessional and poor service. Taking me from pillar to post so I do not cancel my contract and they continue to debit me. This process has been painful and makes me angry. It was easy for them to call me for an upgrade and successfully verify me but when I rejected the offer and opted for cancellation suddenly no one is available to help and I failed my authentication. How when I was correctly verified before? ******** are what define Cell C and their mysterious agents who won’t give out their full details or at least a reference number. CANCEL MY CONTRACT WITH IMMEDIATE EFFECT