Formal Complaint Regarding my formal MTN contract

I am writing to formally lodge a complaint regarding my iPhone contract with MTN. My contract ended on 29 November 2025. More than one month before the contract end date, I visited the MTN store at Somerset Mall to inform them that I did not wish to continue with or renew the contract once it expired. At the store, I was advised to contact MTN Customer Care to process the cancellation. Unfortunately, the customer service number provided could not go through on my MTN line. I returned to the store after repeatedly trying for over a week, and it was then discovered that my line had been barred from calling customer care. An MTN store consultant assisted me by downloading an eSIM on my phone and used the new line to contact customer care on my behalf. During this call, the consultant and I were assured by the MTN agent that my contract had been cancelled. During the same conversation, the agent proposed an upgrade of R125, but this did not go through because FNB did not approve the debit order. The agent said he would follow up the next day to continue the upgrade process, but this never happened, and I did not pursue the upgrade further. However, about two weeks later, I noticed an unauthorised debit order of R199 deducted from my account. I immediately contacted MTN customer service and was informed that my account was in collections. I queried this and explained the entire situation. I was then advised to return to the MTN store. Upon returning, the store consultants informed me that they could not assist and did not understand why I had been referred back to the store. As a result, the store consultant helped me download the HelloPeter app so that I could formally log my complaint. I am extremely disappointed with how this matter has been handled and the inconvenience caused, despite my clear and timely efforts to cancel my contract before its end date. I request an urgent investigation into this matter, reversal of the unauthorised charges, removal of my account from collections, and written confirmation that my contract has been fully cancelled. I look forward to your prompt resolution of this issue.