Manger and employee refuse to refund me my money for electronic component that was not used or installed.

Musina Midas has left me with stories, first I deal with the same employee who shows aggression when I tried returning coolant because it wasn't the right one, now he has never disclose since the beginning I purchased a item that is not returnable, because it wasn't defect and mind you this item was not used or installed. It just happens to be not the correct one, the employee had a choice to either refund me or exchange for the correct item but he calls the manager and he showed unprofessionalism and aggression by not de-escalating the situation. This type of behaviour and mistreatment is intolerable. The fact this was not disclosed, shows the business does not care for the well being of it's customer. I have left the receipt and the item at Midas till my money is returned.