South Africa Post Office Poor Service

I ordered some items online and the supplier sent them via the South Africa Post Office. I have a tracking number and it shows the item in the Witspos hub since the 3rd of March, nearly 3 weeks ago. The destination hub in Westville/Durban says I must call the call center to follow up because they have not received it. When I call the call center they never answer but place me on hold for long periods of time. I sent an e-mail to the customer service of the Post Office and received an auto reply but no follow-up. If I do not receive the package, I will have to pay to have a new one sent.