6 days waiting for LOST BAGGAGE

I flew from Australia into OR TAMBO on SOUTH AFRICAN AIRWAYS on the 02SEP2015 to find my luggage has been lost. I reported this and received a REF no. It is now 6 days since i've landed and still no luggage. I call the baggage call center TWICE a day and the only answer i get is they have no idea where my luggage is. How is that possible???? Luggage is labeled and scanned, how is it possible to have no idea where my luggage is.