Not cancelling contracts and still bills you #investigating

I have cancelled a number with Vodacom on 2016. Due to the fact that I did not want to upgrade this nr. Every month a had phoned in to ensure this number had been cancelled. Sadly it wasn't. I went into the vodashop in kollonade to cancel this nr and I was referred to menlyn vodashop. The nr was finally cancelled in September 2017 and at the same time reactivated without my consent. It is now practically April 2017. Everytime I phone Vodacom, they are investigating. And everytime I hear the same athletic excuse. For the first ti.e the number has now finally been cancelled however I have been paying for something that I didn't use. So annoyed.