Spoiled food from a restaurant and poor customer service

I ordered food from the Mr D app and the food was from Gliss food. When I received my order I ate a wing and took a bite of the wors which turned out to be spoiled. Unfortunately I swallowed the food in my mouth and realized that there is a sour taste and the smell was not good at all. I logged a complaint with Mr D food same day and only received their response the next day when I had gone to the Dr because the previous night I had stomach cramps and a runny stomach. Mr D only offered R50 and an email with an apology but I then sent them another email with a medical certificate showing that indeed I reacted to the food. The last response I got was that they will look into my query and get back to me till today. I then got in contact with the restaurant where I provided all the information they requested including the medical certificate and they advised that they want to revert back to Mr D and they will be in touch. To my surprise I sent another message today and no one is responding to me. I need your help so bad because my health was compromised but no one wants to take responsibility for that. Fortunately I stopped my mom and the kids from consuming the food too after I realized it was spoiled otherwise this would have been a different story.