Refund and exchange policy should be clear

On the 3rd September 2019,I bought NAN Optipro stage 1 formula from Jet Bloemfontein in Bloem plaza mall. When I got home that's when I noticed that there were holes on the foil of the tin and the tin has dents,I even explained to one of the ladies that was helping me that I can't risk giving my baby the formula as it has already been exposed to air,this morning I went to return it and I was told that I can't return the formula, they don't accept it they even told me that as soon as I leave the shop and notice anything wrong with either the disposable nappies or formula, they will not assist me in returning it. Not happy with the service at all,as it is not even written anywhere in those shelves that any kind of formula or disposable nappies should not be returned should you find any faults,I really don't know what I have to do with this formula as I cannot risk giving my son and might be exposing him to food poisoning.