UNHAPPY - Paying more for LESS

I'm really unhappy with Vodacom. Last month - August someone from Vodacom phoned me and upgrade me from Smart S plan to Smart S+, I used to get 500mb promotional data on top of the 200mb per month. I specifically ask him if I will still get my promotional data and he promised me I will. Now almost a week later phoning Vodacom everyday a lady from the Migration department advise, I need to sort it out with the data department gave me a number that is not working, 082151. I'm paying more money for less data. I would never agreed on this upgrade if I knew I will actually loosing my promotional data. What a *******.. I thought Vodacom is better than MTN.. :(