Bad service from manager at Lydenburg fashion world

I bought clothes for kids for my sister's funeral at fashion world Lydenburg in Mpumalanga but it was later decided that the children will not wear black to the funeral, i unfortunately lost the slip as everything was so stressful during the funeral arrangements. I went to the store and asked if i could exchange the items for something else and the Manager of the store was very rude and used a very bad way of talking to me and told me they do not exchange anything without a slip, all the price tags is still on the items. I asked him what the reason is for that because other shopd does assist in exchange items without a receipt as long as the tags is still in place he told me that fashion world is not other shops. I am very disappointed in the way i was treated and now having to stay with all those clothes that the children will never wear