Wrong Information Given

I recently got my upgrade from Vodacom and the sales consultant ( Nelisiwe Manuku) said that my upgrade will come with a R10 000.00 Voucher redeemable at CNA. When i received my upgrade , instead of the CNA voucher i got a Top dog voucher for educational programs to the value of R10 000.00 . This is not what i agreed to at all and I kindly request someone to have a look at the recording of the conversation. I have queried this with her and she sent one email just apologizing and making excuses. I requested feedback and this matter to be referred to a senior manager but until today , i have received no such feedback. Our last email conversation was on the 9th of November 2015. My new contract already started and I have already started paying but do not want to use the cellphone because of this matter. On top of that I am 46 , what am i supposed to do with an educational voucher. Could i as well request a copy of this recording for future use if i decide/need to take the matter further.