Pathetic service

I have just been advised that a parcel I sent service mail to New Zealand in February has still not left South Africa. The parcel I believe is still in Johanesburg. Mine along will many others. I was told the parcel will go out when there is a space on another airline which will go via European country. Why is my parcel going on a flight when service mail is by ship? The post office counters are still still taking in parcels bound for new Zealand and Australia which are simply not going to get to the destination any time soon. If someone from the South African Post Office would like to comment on this, it would really be appreciated.