MTN is taking money that does not belong to them

In December 2020 MTN took just over R3k from my account because my contract expired. My dad has no contract with MTN and no services yet they take between R500 and R200 out of his account every month. I have mailed their ***** email address so many time and what they do is send me a text message 3 days later saying the ticket is closed. To say their service is terribly would be such a massive understatement. This has been going on for months and I think people should check their bank accounts, MTN is just taking money that does not belong to them and is avoiding the subject.