Mr Delivery refuses refund on rotten food delivered!

I've had very good and now very bad service from Mr Delivery.

I complained about food quality of a restaurant and requested a full refund for my purchase - this after having contacted the restaurant in question and stating that they pick up their sub standard food quality - all I received from Mr Delivery was a sorry not sorry text which partially returned my money. So I gave them another chance, and a week later the same food quality issue at a different restaurant happens and nothing comes from it. I have requested my full refund, I even resorted to taking the actual rotten piece of meat to the restaurant myself because it seems like the company doesn't believe me when I complain about the food quality. Needless to say, I have still not been helped, or refunded and I'm driving around with a rotten piece of meat just to make them aware that they cannot allow restaurants to compromise the quality of their food. This is unacceptable.