Nando’s Leaping Frog selling rotten chicken

I bought a Nando’s full chicken meal with 3 sharing sides yesterday evening. I have been feeling ill and had diarrhoea since I ate it. I had a drumstick earlier and all the symptoms are back again. I called Nando’s Leaping Frog to lodge my complaint, but the manager McKenzie was very defensive and kept interrupting me upon my complaint. He has distanced himself from the fact that they are selling rotten chicken and told me it’s food poisoning and that the higher authorities of the food chain will deal with it and not him. I paid for a service from Nando’s and it was not rendered to health and safety standards. Nando’s needs to collect their chicken and reimburse me, as they cannot sell old food to clients and distance themselves from such incidents.