SA post office useless

I have post that arrived in JHB on 2 April 2019 from the US and no one is able to tell me where it is. I am STILL waiting for it! My local post office tells me it never arrived in SA even though my tracking information shows it. It’s only certificates, and not a big package. Don’t bother phoning customer care or even customs as NO ONE answers the phones! My second package seems to be missing too. Any advice on how I can get any information or what must I do to get my parcel?