Useless customer service

I was double billed by MTN for my September 2020 debit on 5 October 2020. When emailing customer care I was told that my complaint was escalate to banking and no further communication was given. When I tried to contact them again, they told me they were aware of the glitch and were working to resolve it. I recieved my statement for October 2020 with a balance of R0 outstanding. Assuming they were going to use the double debit to cover my October 2020 amount, I did not pursue the case further only to see on 5 November 2020 they debited my account AGAIN. When I sent another email to ask why was a debited again when clearly my statement said R0 I received a response saying my query has been escalated. It has been almost 2 weeks now with no feedback further to this. I absolutely frustrated with MTN and their lack of concern for their own mistake. They don't seem to be interested in correcting their error and refunding my money. Pathetic service, so disappointed.