Terrible service at PEP Home

I went to PEP Home at Bluff Towers, on the Bluff in Durban, KZN. I baught 3 outfits for my queen size bed, 2 of them the same style just different colours. All 3 of them consist of a duvet cover and 2 standard pillow cases.

I home unpacked and put them in the washing machine. Hung them up, only to realize one set, of the two same sets, doesn't have the pillow cases. I phoned them the next day and I was told they can't help me without the packing, which was literally a small paper box which I threw away as soon as I unpacked. I have the receipt, with the barcode of the item. All I need are just my two pillow cases but they refuse to help me because I don't have that mini paper box. It's completely unacceptable at the treatment I received at this PEP, especially after spending R2100 and some change, to peinalised for that.