Being charged for no services

I curse the day I took a wifi contract with you guys, I took a 1gig which was supposed to be R100 a month and it shot up to R750 when I went to complain they told me I exceeded with the airtime which was news to me because no one explained that part fine they changed it and than I took 1 that was on special 10gig for R199 but it will finish in 2 days and went to the branch to ask they told me I don't have coverage on LTE but when I took it they didn't explain that but was paying every month for the service I was not getting and they said I must fill a form on an iPad accounts department will call me back until today nothing is happening but they still debiting my account I'm sick and tired of your poor service Telkom I wish your company gets shut down or people sue you until you go bankrupt