Bad Cell C customer service

I cancelled my contract with Cell C on 31 May 2025, after almost 3 years. I asked to go on "pay-as-you-go" after that. The cancellation was confirmed telephonically. I payed my last month's fee end of June. I had to load data and airtime regularly in July to be able to even send a whatsapp. End of July money was debited off my bank account by Cell C. I reversed the payment and contacted Cell C customer services at my own expense. They gave me a case number and after talking for about 30minutes and being transferred to different people, they dropped the call. I phoned customer service again later that week and explained everything AGAIN. The person then said that they can not explain the outstanding amount and will look in to it, but someone from Cell C will then get back to me. Then on a Sunday morning at around 10:00 (while I was in church) Cell C contacted me from a number I could not phone back. They only phoned once and then sent me a message to say they could not reach me. On the following week I phoned customer service again with my case number and then spoke to them for at least 60minutes (while using my own airtime once AGAIN). Once again they said that the outstanding amount could not be explained and that some one from Cell C will get back to me. In a previous email Cell C said the outstanding balance was allocated for "smart data internet" and "content services" while I was only on "pay as you go" and had no data or airtime except for what I loaded. When asked what smart data internet or services I had received while on pay as you go, no answer could be given. I also emailed twice and received no response to explain these costs to me. I even went in to a Cell C store to try and get answers for the outstanding amount but they only said they could not access this information from a store and I need to contact customer service AGAIN! Then I was handed over to Nudebt apperantly, who deducted money from my account last month, without authorisation, which I also had to reverse. Now they are saying they are going to deduct money again and still Cell C has not been able to explain these outstanding amounts to me for wich they are now adding interrest too every month and subsequently causing this to reflect badly on my credit score?? How is the not absolute terrible service? This shows only an interrest in money and NO customer service!! Very poor!!