Goods disappeared

So I bought something from Joberg it was an over night courier to Cape town I tracked down the parcel and was said receive in Cape town depot the next day but to my surprise I didn't receive the parcel I was told unfortunately we can't find it and won't refund because it wasn't insured mind you this was the second time my parcel disappearing in their hands.

My question is what happens if these people find our parcels later what do they do with them and how does a parcel disappear after being said received it's very suspshy.

Someone has to look into this I'm so disappointed