Disappointed with Telkom Mobile Service

Trying to get Telkom Mobile billing department to contact me with regard to something that I did not agree to but was billed for seems impossible. I was contacted once, on the 07th of August 2015 and I was told that I would receive a follow up call but that did not happen. However it was ironic that I got contacted about a new deal just today and I feel like my current contract query is being overlooked. I reported the issue on the 25 of July 2015 and I'm afraid I'm going to be billed for something that I did not make use of which is rather upsetting. I've contacted the customer call centre on numerous occasions and I've logged many online queries and yet nothing.