Post Office has poor service delivery (some of their agents are rather useless!!!!)

Our parcel was cleared at the Johannesburg customs on the 19th of December. The parcel was incorrectly sent to Randburg and had to be sent back to customs. We were promised delivery a week ago and still have not received the parcel. Furthermore, no one is able to assist with regards to when or where the parcel will be delivered. Certain call centre agents have a bad attitude and simply answer questions with the phrase "I don't know." I was asked to call back on thursday to get the status of the parcel. As a small commodities trading business, we cannot afford this kind of delay and lack of information. Ref: HJ ********** 25US / II ********** 06ZA