unexplained amounts debited for a service I requested to be cancelled in Novemeber

I app**** for a 5GB plan on August 24th, 23rd, for R595, in accordance with the sales agent's phone conversation. After calling the customer service line this morning, I discovered that I had been paying an extra R200 on my account for the last three months. The agents put me on a higher plan with more costs, so I am asking for a refund for the extra money I didn't want to pay for those three months complained logged in November 2023.....Since then my account was never cancelled after requesting cancellation on numerous occasions....I was billed twice in the month of February R1200 and R900 including November and December 2023 .My simple request was to have this contact cancelled ,router collected and no of the above was made instead my account is debited with high amounts. I have reported this to the call center and have since not received any feedback or any call from any manager as promised. Who gave urll the right to debit my account from November till March ,,,can I have this **** cancelled and my bank account credited ASAP.