Not getting any response from Telkom

I would like to report Telkom with regards to billing me incorrectly and not getting any response on my refund. In April 2015 I took out a cell phone contract and a data contract which included a free wifi router. I returned the router the next day complaing about the data that vanished. The manager in the store tried to explain but one could clearly see that she does not know how data works. The contract was for 1G and addtional 3G night time. She tried to explain that my data will be given prorated but could not explain how 1G vanished without receiving the full 1G. After much debate it was agreed that I would cancel the data contract and will not be charged a cent as I returned it within the cooling off period of 7 days. In May 2015 I was charged and in June 2015 as well. I logged a complaint and the subscription was refunded. In August an amount of a R1072 was deducted from my account and when i queried it I was told it was a penalty for cancellation of the data contract. My question is how can I be refunded my incorrect subscription for the two months and then later be charged a penalty. Please assist (case number ***8 logged 04/09/2015) no response from Telkom to date