unauthorized billing of my account

I have sent a review concerning Telkom and it's WiFi bundle deals. I was told to send my information and they will contact me but still waiting to be contacted. I don't understand this contract because it was R199 * 24 months. After 10 months I'm bring billed R299 and was told I was using "out of bundles" which is a lie because I didn't use any out of bundles last month and was still billed R299. I'm sick and tired of being ****** by a reputable billion rand company.