They owe me money!

I am totally digusted with the service received from Supersonic. I canceled my account 2 months ago. They were told to collect their router, which they did. Nevertheless, they preceeded to debit my account for R2499. I have not managed to redeem my money. Thereafter, they debited my account for a further R798. Have spent hours on the phone trying to get my money back. Every time they say that the matter has been escalated and that I have to wait 21 days to get my money back. It has been more than 2 months now waiting for the more than R3000 that they owe me. This is totally unacceptable! Do not do business with these people!