Impossible to cancel Vodacom Insurance

So, Vodacom has ****** R180 (+/-) from me since January 2019 - because they *********ly put Vodacom Insurance on my bill. I've tried for 19 months now to cancel the Vodacom insurance, but it seems IMPOSSIBLE!! I have literally tried every single avenue... To date they owe me close to R3500 for this mistake. And, because no one is getting back to me regarding this issue, (For over a year now I've just been passed on from one person to the next...every time being promised that I will be phoned back. In 19 months, since my first complaint, NO ONE from Vodacom has called me back regarding this. Not ONE call, message or e-mail). Due to the "no reply", and STILL to this day paying R180 odd a month for the Vodasure, I decided to stop paying my bill last month - with the hope that someone from Vodacom will get back to me. Instead, they blacklisted my phone... To anyone ever thinking of getting ANY contract from Vodacom, I STRONGLY urge you to rethink. I have, in my lifetime, never dealt with so much lying, *********ness and incompetence.