Worst service

I went to purchase items on the 3 for 2 special at Edgers in George (Western Cape). They refused to sell me an item that was on the 3 for 2 sale claiming that they can’t because on the system now it shows that it is on mark down, I should look for something else even though they acknowledge that the item is on the 3 for 2 sale. I explained to the manager that I want that specific item and since I found it on the 3 for 2 section. She told me they can’t do anything about that I must look for something else regardless.