Calvin Klein T-Shirts Shrink to Child Size After Just One Wash

I wore each of the two t-shirts I bought from the Calvin Klein store at Emaar Mall only once, and even though I followed the washing instructions carefully, the t-shirts shrank significantly, nearly down to a children's t-shirt size. As a result, I can't use these products at all.
About a week after purchasing the products, I took them back to the store, explained the situation, and requested an exchange. The t-shirts were sent for inspection, but the result came back negative. I was told at the store that there's a written result of the inspection, but I haven't gone to pick it up yet. I don't accept them treating a product that shrank this badly this quickly — despite being washed according to the instructions — as if it were user error.
I'm disappointed to experience this kind of quality issue with products from a brand like Calvin Klein, and by the store's negative response. I am requesting that an exchange be made for my two t-shirts, which have become unusable, and that the problem I've experienced be resolved.