Expired goods

I bought two 850g tins of Isomil 1 at Shoprite about a week ago. Only to find that one of tins the seal was already broken and they both had an old expiry date for last year 2019-06. I am very unhappy because my 4month old son has already consumed one of the tins. I am under a lot of stress because of the medical bills and extremely grieved. I am very unhappy with the product and Shoprite. I would like to be reimbursed for my grievances