SA Post office bad service !!!

I bought stuff from the USA, My package was delivered to the post office. 1st it was lying there for over a month before the notified me about my package. that was in Des last year. I've already paid $115.90 (R1667) SHIPPING FEES INCL. When I wanted to collect my package I had to pay the Post office another R980 for shipping fees. I feel that the shipping fees is already paid and to pay almost another R1000 is crazy. Ive then send the package back to Post office head office (JHB) for re-assist. Today its 5 months since it was send back and still i have no answers. Ive tried to phone the head office so many time, they just keep you on hold. How or who can I contact to get this matter resolved.