customer service not good

I have for the last 7 years since living in an area near Checkers Grey Owl been shopping there spending an average of R800 every week. About 2 weeks ago I bought some very expensive chocolates there as part of a gift to someone. Unfortunately yesterday I noticed that it had an expiry date of February 2025 so I tried to return it today. When I looked for the till slip I could not find it but as the item was unopened and in perfect condition I decided to try and exchange it when I do my weekly shopping today. To my disappointment I found there was absolutely no willingness to assist me from customer services as well as the managers side so that is R169 down the drain.