Telkom Mobile Bills you as they please

I upgraded my Telkom Mobile cellphone on the 11th of Dec 2015. I went from a more expensive package to a cheaper package. I was told by the Telkom Mobile Agent at Highveld Mall that I have to pay him a cash upgrade fee of R350. He phoned me about the upgrade fee twice more and I explained that if he would provide me with an invoice I would pay the fee over via EFT. He said he cannot do that he needs me to come into the store and pay cash. I took the matter up with the Telkom Mobile call center who informed that there was no upgrade fee to be paid. I wanted to know what they were planning on doing about their store that is **********ly trying to ****** money from me and the reply I got was that there is nothing they can do. I left the matter at that BUT at the end of the month I received a Telkom Mobile account for an amount of R1,083.42. I have been trying since the 20th of January 2016 to get the additional charges refunded to my bank account and I am still waiting. I am very disappointed in Telkom Mobile - I can no longer recommend them to anybody as this is the kind of *******, incompetency one then has to deal with afterwards!!!