Refuse to return an item bought 21 days ago

An item was purchased on 07/01/2018. Upon attempting to return the item (incorrect size) at Woolworths Mall of Africa, they refused to return the item. All three managers on duty refused to return the item as the system had discounted the item to R0.01. The managers claimed that any items bought during the quality sale could not be returned after 30/01/18.