Cell C contract cancellation.

I have a data contract with cell C and I am suppose to R149 for a month to month contract that I took up on the 17th of April. When my contract ended (13th March 2021) I called in and cancelled and I was told that I have to give a notice which then meant that the contract will effectively be stopped on the 17th of April 2021.

When I called to do and upgrade I spoke to a guy called Itumeleng Mabaso who is an agent of Cell C to help me get an upgrade my contract. He did assist with the upgrade however he opened a new line for me instead of upgrading my all line. Upon receiving the sim card he sent I emailed him and told him that he opened a new line and I did not want to loose my old line. He then said i should not use the sim card it will be collected by the courier that had brought the sim card. He then went on to say he will cancel that contract he opened however I am still being debited for that. I emailed him to ask what is happening because I am being billed for this contract and the billing is way higher than what I would pay for if i had gone through with the new line that he opened. He said I should call cancellations department on 084143 however the number is not working.