Failed to cancel contract after years

About 5years ago i was offered a special deal on a wifi router. I was contacted telephonically so everything was done over the phone. Due to the area where i stay, i didnt want to use telkom as we have no coverage. The lady on the other side of the phone ensured me that i would be able ro use the router using mtn roaming. Immediately when i received the router i noticed that it was not working. I called customer care and they informed me that the router cannot work on mtn roaming. Since ive had the router i have NEVER been able to use it. Ive been to the tekkom store numerous times over the years and even received numerous different case numbers. To this day i still experience deductions from telkom as they have failed to cancel the contract for the past few years. They have also failed to reimburse me with the cash that they deducted from me. I am fed up with telkom and i will not suggest their service to anybody