No box no exchange!

Purchased a heater, a week later,1 bar was not working. I returned it to the store with a till slip however not with the package. Clicks Woodlands branch did not have the item however were willing to e change. They contacted Parkview where they said I could come. On my arrival I was refused an exhange, let alone a refund because I did not have the box. I threw it away thinking I trusted what I had purchased from a trusted retailer. She was outright told me she won't exchange unless I had the box. That would be the end of me and Clicks!!