No food?

I jave gone to kfc in cullinan, kfc in moreletapark and kfc in elarduspark. I have never been able to receive what I want. Everytime I go, they either dont have chicken, or I end up having to move out the drive through and having to wait over 30 minutes for my food. I find it very rediculous and will not support KFC anymore. I have asked several of times if they cannot give me a viucher for not being able to give me what i want, or for replacing the food they do not have with something else, but i get poor responses each and every time.