Bad service

Good day,

On Saturday me and my friend we went to KFC Orlando 645 drive thru and ordered 2 All Star Lunch box for R119. 80. And when we already drove few kilometres away we realised they did not put in wings, it was only a piece of chicken, burger and chips which could have cost us R49.99 each and we would not have driven back because we were already a bit far from the store. my concern is it is not the first time it happens and at the same place therefore you need to look at it as it might be happening to so many people. So I'm not sure if they are intentionally doing it or its just a mistake and if so how because you order now and in few minutes or seconds you collect from the other window?