Telkom avoiding paying out my refund.

I took a contract out about 2 years ago and telkom have been debiting me for two contracts instead of 1... Ever since I have been trying to get my refund and they keep closing the matter for various stupid reasons. I have sent through all documentation and they keep closing the case and nobody ever calls me back even after the call gets dropped probably on their end. I'm am beyond frustrated and would just like my money back so I can never be involved with them ever again.