refunds policy

I purchased a dress for my daughter.the purchase receipt has been lost but the dress still has the pricetag attached.Ive now been told by the staff at WW westgate thast I cannot even get a credit voucher.I am supposed to take another CLOTHING item.does the customer not have a right???why should I be forced into purchasing somethig I dont want or have a need for now?this is very disappointing service.The sales lady asssiting me was extremely rude and wouldnt listen to my queries.as per her,WW doesnt not issue credit notes.