Poor Service and wrong package

I upgraded my contract with Cell C in September this year. I did the whole process telephonically with an agent and we agreed on a specific package of an 8 gig pinnacle and phone model for the upgrade. I specifically ask the agent if he is sure the package he is offering me is possible and he agreed. I was informed the new package will be effective from December. I got an sms in the first week of December from Cell C notify me that my new package is effective but to my surprise the new package was not what we agreed on with the agent, the package new package activated was a 5 gig pinacle contract. I logged a complaint on the 7 December 2020 and was given a reference number and told my case will be resolved within 48 hours , its been two weeks now and im being sent from pillar to post by Cell C customer care agents, everyday when i call im told the case is still in progress. I was told by one agent that they will retrieve the recording for the day the upgrade was made but it seems like it takes forever to get a simple call recording to confirm what was sold to me. Im highly disappointed and angry with Cell C