Data contract cancellation

I took out a month to month data contract at the MTN Rosebank store on the 30th of January 2024 and I returned the router and requested a cancellation on the 06th of February 2024 at 12:23 . To my surprise I was debited on the 15th of February and I have not been using the service as it was returned to the store.

I called their call centre on the 16th of February and I was told that the contract is still open and I was told to return to the Rosebank store. It had been a back and forth since then and I am not receiving any assistance. I have reversed the debit order on my side because I cannot pay for a service that I am not using. I sent an email to their complaints department and received no response(Reference number: 2be8915c-ccbb-4b78-aa27-1a39885ad14e). I am now being billed Again for the month of March for a service that I am not using. I call their call centre and consultants hang up the phone in my ear. This is very unprofessional and very bad customer service