Telkom rippoff

Hi i am having a big problem with telkom mobile for the last 3 months now. I am being billed for data that i did not buy, and when i contact them they dont seem intersted in resolving my query. iI currently have 2 Wi-Fi router contracts with them, and somehow im being billed double my monthly subscription,because according to them im buying once off data bundles on both numbers. please if someone can send me in the right direction so that i can get assistance with this, i will really appreciate it.