Not Honoring Promoted Deal

I am at wits end now! I have been trying to upgrade since December 2014 now and all Vodacom has done thus far is pass me on from one call centre agent to another. When I did end up speaking to some sort of Manager I received empty promises and still no joy almost 8 months later. I skipped 2 upgrades already and just kept paying my contract month to month keeping my old phone. In short I was offered a deal that was on promotion in December but just before the deal expired Vodacom pulled the deal even though I was promised they would not do this (all communication was confirmed and recorded). Vodacom admits they were at fault but yet does nothing to try and salvage a a customer and offer compensation similar to the deal originally offered. Sad part is I would settle for the same handset that was offered in December even though it is a model that will probably be replaced soon as it is almost 8 months later. I NEED to UPGRADE before the end of JULY and want someone with AUTHORITY to make DECISIONS to handle this and RESOLVE MY PROBLEM. I am extremely upset and can't believe that this issue is still not resolved!!! I am done with excuses and passing of the buck, fix it NOW!