Refund for a canceled contract and unauthorized Debit Order

I upgraded an existing line, but eventually canceled the upgrade due to waiting time, as there was no stock available at the time. I then opted for a different device for an upgrade. Telkom continued to supply the initial device (canceled upgrade) and added another line to my existing contract, which I had not requested. However, I returned the device to their store for cancellation, and I was advised to wait at least two months for the cancellation and refund to be processed. Six months later, they continued debiting the account. Until I reached out to TMB Support, the matter is still not finalized. Instead, they debited a once-off fee to the value of the device that was returned (unauthorized) Now, I am battling to get a refund for a canceled contract, including the one-time fee for the value of the returned device. A dispute number ***4 was opened but rejected without processing a refund. ***.

I want to cancel all my Telkom contracts due to poor CRM management.