Another lost parcel at the SA Post Office

I ordered something from Amazon and for the first time in years they sent it via USPS, which uses the SA Post Office to deliver it in SA. Amazon's tracking says it arrived in SA on 27 February. The Post Office says it has not arrived. Who do I believe?... Amazon of course. I waited more than 30min before the Post Office answered my call. Unacceptable!! I fear that I have lost another parcel through the Post Office. Be warned, rather pay more (much more) and courier your parcels to SA. The Post Office is not worth the frustration.