Buy & Get promotion lies and misleading

I saw that Samsung had a Buy and Get promotion. As we needed an airconditioner and a fridge I was interested in the deal where you buy a fridge and then you get a voucher that you can redeem on an other product. Knowing that these promotions can be misleading most of the times I phone the people at the Samsung Buy & Get twice to make sure that I will be able to redeem the voucher on an Airconditioner (AR4500) before I went to buy (the fridge with Voucher deal) as I only specificly wanted the Airconditioner. Both times there representatives asured me that the voucher will be redeemable against the Aircon. So I went to buy the fridge and then waited for my voucher to emailed to me. When I recieved the voucher I tried buying the Aircon as planned but it did not work. I then phoned the Buy & Get promotion line and I spoke to another person that said that they will sort it out and get back to me. No one did. A week later I phoned again. This time I was told that they did not have stock of the Aircon's and that I should just wait untill they get there new stock before the Black Friday specials, and then I will be able to buy it with the Voucher. That was another lie. Two weeks after that and because the voucher still did not work I phoned them again. This time I spoke to a Bernice that said she will escalate my issue and that there are many other people that has got the same issue with the vouchers not working on the Aircons and that she will get back to me the next day. She also did not get back to me at all. A week after that I phoned and asked to speak to a manager (Quinton) that ten told me that I cannot redeem the voucher on an Aircon. I was shocked at this news as I confirmed this with them before I went for the deal. So they straight out **** and misled me into buying the fridge. Quinton then just said that he is sorry and just left me hanging. You dont expect this from a company like Samsung. It looks like Samsung is now just as ******* like the rest of Africa. Now I am stuck with a voucher that means nothing to me. I wont hold my breath for them to respond because they probably wont....