No coffee freezo PnP

I went to pick and pay express in howick at the BP garage to order a iced coffee freezo at the wild bean café,just to be told that they don't have it in stock. They've had it displaying on their big screen for about 5 months now,and everytime I went there to order the same thing , I get told the same excuse.I want to know what's the reason for displaying something on the menu ,if you don't keep it in stock.. Isn't it false advertising?