Possibly ********** Promo & Poor Service

I am appalled with my experience this morning, with a brand I have been loyal to all my adult life. I was concluding an online purchase for the Samsung 9kg AddWash Washing Machine for R8,999 with free delivery on their Buy&Get promotion (Receive a R3000 voucher in this instance) from Samsung directly. I added the item to my cart and proceeded to checkout. I wanted to use the R3,000 voucher to purchase myself a pair of Galaxy Buds+. Once I got to payment, I received a message saying the item has been removed from my cart, as there was no stock. I fortunately had a few other windows open with the same special and immediately took a screenshot of it, displaying the Promo with the Voucher, and my item in the cart. I then called the closest store to me (Samsung Pavilion) who confirmed they do have stock and at the same price plus a R250 delivery charge, but don't have the same voucher promo as it was a franchise store. I called the support line, chatted to an agent who told me "Ya, if it says we don’t have a stock then we don’t have a stock". I asked to speak to someone more senior as this response was pathetic and was told "Even if you speak, nobody can tell you anything, you must just follow us". I ended the call, and called the promo line, who were pleasant, but also told me "maybe during the year we will have the same promotion, you just have to look”. This is unacceptable. I demand I am given the same deal, as there is stock available. Please can I be contacted urgently. I have the screenshots with time stamps etc. but was unable to attach to this review.