Vodacom upgrade dept customer care non-existent

I upgraded my contract via a call back on or about 19.11.2018. From 10 gig R498 a month to 10 gig at R149 a month. Contract did not start on 01.12.2018. Called and complained. Was informed that the upgrade was scheduled for 31.12.2018. No-one vould supply a reason. Told them I was not satisfied. Nothing was done after speaking to more than one call centre agent. Requested that a manager contact me, which she did. She promised to get back to me. Never did.... I called again and was told that I would be called back. Still nothing. I followed up again today and was told that the upgrade still has not been done. Tge upgrade still shoes open... Instead of paying R149 I will again pay R498 this month. Call centre cannot assist and Upgrade dept closed at 17h00. They cannot ask someone to call me back tomorrow as their system does not allow it. I am extremely unhappy!