McDonald's bluff- poor service

Went to McDonald's bluff, durban twice now within a few days. First day, they gave me the wrong order. When I complained to the manager, he said he can't do anything and font have a driver to deliver the order. He said when I come in the next time, he will help me, but everytime I went there, he is not available. Today, I went through the drive through and asked for sweetcorn, they said out of stock from Thursday but, I told them that I bought on Friday, so how come it's out of stock, no answer. They are lazy because it takes longer to make the sweetcorn. Really disappointed with McDonald's bluff.