Customer service and Billing

I cancelled my SIM card in April and stopped using it . In June took a payment of R750 from my account because apparently I was still registered. When I call customer service they confirm that they see the cancellation request and they don’t understand why payment was taken. I’ve been calling for almost 2 months to get my money back but still getting the run around that the billing department will call me. The worse part is that they still attempting to take payment this month as well for my cancelled services 😡😡😡😡😡😡😡I WANT MY MONEY BACK