Misleading advert - Staff clueless over their own ads & promised voucher

Samsung had a Buy and Get special running on their website towards the end of last year for an R10k voucher if you bought specific items, I believe this ended 31 Dec 2020. Around Feb/March they kicked off another R6K bug & get a voucher special on specific items, this is when I decided to purchase a fridge online. I bought the fridge because of the advert, tried to claim my voucher the same day cause i bought the fridge case, the system was unavailable. Contacted the "Samsung Promotions Team" *** (voucher claims), they said someone will attend to my request if I emailed all the details (i have trail emails). I did that now they are telling me that the special ended in December and cant assist. I sent them screenshots of the advert that this was different to the December one - no one seems to know about this R6k voucher add. I bought the fridge because of the promised voucher. Every time I call the Promotions team (voucher) department(Altron) they are escalating the matter and will revert. No one ever calls back. Today they said they cant assist because they no longer have access to vouchers. I need this escalated to a different team for resolution.