Rotten patties & lettuce not fresh

I bought two burgers from chesanyama, the burgers that they delivered were not fresh. The patties were tasting sour as if they were rotten. we just ate half and through the rest in the bin. Today when I complain at the shop they told me that the realised late yesterday that the patties were rotten, but they cant do anything to help me because I only went today. I tried to explain that I had a meeting yesterday that's why I didn't go to the shop but she said they cant do anything.