Rotten chicken fillets

For the 1st time I got disappointed with Oxford. I have been their customer when I was working in Jacob's, I used to buy in Bluff one but for the past 7 years I am using Hillcrest one. I bought couple of meat including chicken fillets on 25th Jan if I am not mistaken and I cooked chicken fillets on Sunday, the 2nd and they were off. We couldn't even eat them. I am not sure if other trays are ok because yesterday I cooked mince and it was good. But as for fillets I am not sure, however if it's off I will carry it to the shop since I doubt I still have slip