Mail missing

We had our post office box locked by accident about 6 weeks ago. After battling to get it re-opened, they eventually opened the box two weeks ago. Unfortunately our mail is not being delivered. This is a paid service and they are not delivering our mail. We have complained to the Wonderpark branch and they say they are not responsible for the delivery it is the central office in Pretoria that are not doing their job. Everywhere you go in this country the service delivery is bad. What can we do to receive our mail?