Vodacom Meyersdal - worst decision i made going there

I upgraded my Vodacom contract in December 2017 at the Vodacom Meyersdal Branch. I made it very clear that my contract was to remain the same, i just wanted an upgrade done as in July 2014 i took a promo which gave me 1 gig for R49.00 per month and i did not want to lose this. In January 2018 i noticed i did not get my 1 gig and my contract had changed. I went to Vodacom and was told that instead of upgrading my contract they changed it to pre-paid. When i told them this is not what i wanted they changed my contract back to what it originally was. The reason i lost my 1 gig for R49 was because my contract was changed. i told them this was totally unacceptable and they need to reinstate the 1 gig at R49-00 as i made it clear that i did not want this tampered with and i will not pay R149.00. Deon du Plessis (Manager) at Meyersdal has been promising me from January that this will be rectified. Well it is now April and my account is still not sorted out. I lost the 10 gigs that is awarded to you when you upgrade in January when they changed my contract back to the original contract and not the prepaid. When i complained they gave me back the 10 gigs. In Feb and March i was charged R599 for the free ten gigs you get when upgrading. This has all been reversed but now my 1 gig at R49 is still not sorted. When i contacted Deon beginning April, he now says he cannot give it to me because it was over two years and the two years is over. This was not a contract but a month to month promo. How can it be two years from July 2014 to December 2017. He has now washed his hands of the mess his branch has made and said there is nothing more he can do. I contacted Vodacom and when i explained the two years cannot be right, they said that they still cannot reinstate the 1 gig because the promo is over. The fact is that Vodacom messed up my account and now they refuse to sort it out. I have been a loyal customer for years (i have been with them so long i still have an 082 number) but they cannot return the same to their customers. I do not see why i have to pay R149 for a gig when they messed up my promo on my account. i am very unsatisfied with Vodacom and unfortunately have to stick with them until March 2020. i totally regret ever walking in to the Meyersdal branch in December 2017, when i previously upgraded, i went to the Alberton City branch and there they did not touch my promo but just upgraded me. I wish i went back there instead of Meyersdal.