False advertising!

Went to Makro yesterday 27/05/2020 & purchased an epson printer I paid R2699 after shopping i rushed to the car, on my way to the car I saw a board which says cashback on purchase of epson eco tank printer, but i had to rush somewhere i could not go back in to query as to why i did not get my cash back. My fiance called Makro Springfield today & spoke to the sales person who helped us yesterday & was told that the promotion ended in March. But why is the board still up? It is almost a month now & the board is still up!!!!! This is ridiculous to pay so much for a printer & not get the promotion, especially when the board is still up & states there in bold!!!!