Incorrect goods sold

I visited the BP in Soweto by Mzimhlope hostel and went into to purchase from there wild bean cafe, I ordered a double cheese dog which cost me R24.90, I have purchased it from a number other BP wild bean cafe, but I was stunned by what I found when I got home, firstly the hotdog needed to be a footlong hotdog and the Vienna but all I found a normal size hotdog with a normal cheese Vienna, I then asked myself what does there normal cheese dog look like. Why are they selling the incorrect quality of a good but pricing it the same as the other outlets. This was so disappointing what is this about instead of selling the incorrect stuff why not say we don't have a double cheese dog but we have a normal size cheese dog and price it different to what the original double cheese dog is priced, could someone please look into this and give feedback. I really felt ****** as that was not what I wanted, I could not take it back because firstly it was late and didn't have transport to take it back.