Terrible service and False advertising

Cell C, your service is bad, you change a contract in its time to something totally different and the contract was taken out for the all net minutes, now you changed it to 200 all net minutes and 400 cell c to cell c, my work is not just cell c and every month i now have to go into the shop and pay more so i can do my work and on top of it all, I'm on wifi so it is not suppose to go off my minutes because it is free wifi calling and when I queried it, your shop people just say it happens, so false advertising as well.