False information

I took out a mobile contract on the 28th December 2018 at the Greenstone Mall store after the consultant explained everything to me as I was not sure of the terms and the Samsung S8 device. At the end of January I recieved my invoice which included full payment for the month of December. After calling Telkom Mobile i was informed that even if you take out a contract on the last day of the month you will be charged for the full month there is no pro rata applicable and i need to go to the strore that sold me the device. The consultant at the store as well as the store manager is not even aware of this - they are under the impression that it is a pro rata payment due!!! How many cleints have been ****med by this???? How can i be charged for something i did not have? this is theft!! I have been trying to sort this out with Telkom since the beginning of January and everyone is passing the buck and no one sems to care... I have also just found out that the insurance option for my device was never explained to me so that i could make an informed decision and now it is passed 30 days so i cannot take that option. The whole purchase of this contract has been made into such a mess and now i am stuck with it for the next 24months and the bad service from all sides that comes along with this phone. I think that Samsung should be made aware that the consultants and even store managers need training on the product before selling it to customers as this is a terrible reflection on the product and brand. I will be taking this up with Samsung as it is ******** and unjust.