Damaged dress

Yesterday while I was doing my.shopping at ShopRite Mdantsane city.I picked up domestos and it spills on my dress and it was ruined my dress with pink marks as it navy in colour.I reported it and the manager make fun of me in front of customers.All want now is my dress because its very expensive Nd it is new.How can ShopRite pack damaged good especially the chemical stuff like domestos