Shoprite liquor ruined my heritage day

I just come from a horrifying experience at shoprite liquor watergate.. Castle is running a promo for a tray of castle beer you get a springbok sweater for free. The shop is packed with trays of beer but they only had 2 sweaters and a long line of peopIe waiting for it, 8 specifically went there due to it being my dad's birthday today to get the sweater as well.. As I approached the manager to find out when they would be getting more stock he immediately said the promo is over last week. I then told him with the paper in my hand that it's advertised until the 6 October. He just disregarded me. I approached another manager that did the exact same thing but she was rude about it as well and wanted to run a show infront of the other customers and all I wanted to know is if I could come back for the sweater. Please tell me is this the service meant to be offered? Why would you advertise a promo like this if here's no stock 2 weeks before its meant to end? My whole day is ruined on heritage day of all days early in the morning. Please let me know what will be done.. If needed I have my slip as well as the advertised promo.. All this hassle and bad customer services