No stock on the shelves

I went to Pick and Pay on Saturday it was the holiday, i went to buy myself a box of a Robertson wine that was on special that started on the 20th of March till the 24th of March 2026. When i got to pick and pay the was wine was already finished, i asked one of the staff members and they said it was finished. Mind you its a Saturday, a Holiday and its only been a day since the special started. I checked the pamphlet if it said while stock last, but there was nothing like that. I was so upset i ended up buying something that i did not like.