Absent service with no recourse

I am extremely disappointed with the service I've received from the SA Post Office. I was sent an important time sensitive document via International Registered Mail. The document arrived in the country in November 2020. I've have been trying ever since to actually learn of the whereabouts of the document, with no success. I have visited the local Link Hills branch 3 times, only to be turned away without any further assistance. I have phoned the Durban exchange office over 20 times and these calls were never answered. I have phoned the national helpline twice and have held for an average of more than 30 mins on each occasion, left listening to the annoying automated recording but never actually reaching an agent. I have emailed the helpline twice with no response. The tracking facility on the website has reflected the same status since 1 Dec 2020. We depend on this monopoly for critical services that keep the country and its economy going. One would and should expect better service.