Poor TELKOM service -

I have had a contract for a long time. The past year the service has been extremely poor with calls dropping continuously. I reported and was told that they knew the tower was faulty but do not intend fixing it. I therefore decided to cancel my contract only to find that every time I phone they keep on dropping the call before I could speak to and agent. I tried cancelling my contract in store but they insist it can only be cancelled through the service agents. I am fed-up but still bound!