I'll mannered manager

I took non perishable food item to games in thohoyandou to exchange or refund as it was the wrong flavor purchased. The department manager refused to do an exchange making excuses that they do not exchange food items beyond 7 days. I told him it was not a perishable food item, was in original packaging, unopened and with the receipt, but he refused. Then he falsely alleges that I any have purchased it at another store and brought it to games to exchange! I told him to scan the receipt and the barcode on the bottles to see if the stock was from there store but he replies That all bottles have the same barcode! I asked him to show me the policy documents on which it says that refund or exchange is not allowed on food items that are non perishable and he said they do not have a copy at the store cos they can't be showing every customer policies! He gave me his name as Thomas. He kept making silly remarks as I may have stored the bottles in undesirable places and that it may not be fit to resell at the store to other customers! When I walked around the store I seen many bottles in conditions which may not be desirable to resell aswell as expired chocolate on the shelf! The attitude stinks and obviously he has no knowledge on how to handle customers, be aware of store policies and regulations. He went on to say that I must just give away the stock to someone else. For free. Just distribute it! N he even went to ask me if I have a policy document at my store, which does not even relate to the situation. Just pathetic.