Do not get any important mail

We have been staying in this new area for 3 years and in the 3 years our post is always late or never arrives. I was supposed to get a letter from the court February 2015 and the acceptance letter from ym daughters school. Its been months and still nothing. Plus what is this problem with them using ERF numbers when the City of Cape Town gave us house numbers with the DEED OF SALE. Its the first time i heard of this that the Port Office can only deliver when there is ERF numbers on it. If you give that address with an ERF number to a business they look strange at you. But i want to know when will i get my post cause the way things look now i will never receive it. Last time i send an complain to the Post Office services directly and the lady that called from the Depo was very rude on the phone towards my mother. Is not their jobs to do. Cause i work and if i do not do my job i will be forced to leave. So why does the people at this Depo not do their work?????