Selling rotten food. Poor customer service from management

I bought chicken ( Chic portions) as per description on the till slip this morning, 17th January 2025. To my surprise when I was so looking forward to have my lunch, it had weird smell when i was warming it. I ignored the smell and took a bite and then It was so not fresh, when I say not fresh I mean Rotten and I took it back. I asked for a manager the lady at the front tills (not the cashier) (I am not too sure what her role is) immediately went to the till and gave me my money back and then manager suddenly appeared and she pointed me the manager, I told the manager about the issue and he smelled the chicken and said "it's not fresh" and carried on with whatever he was doing. I asked him if he was even listening to me and he turned and looked at me and asked "but you got the refund right?) no apology from the manager or anything of that nature. I told him for the second time that I took a bite from that rotten chicken, assuming he probably did not get that. I told him I could get sick from that and all I got was if "well if you do just bring proof and the company will pay"