Postnet Brentwood ruining my business reputation

I've been using Postnet to courier my goods up and down the country for some time now. . About 2 months ago I sent an item to a client which landed up at a Pretoria Postnet with the same Mall name as a Postnet in the Vaal. I have repeatedly spoken with Renier who is the guy I deal with at the Brentwood park Postnet as I use themy at least 3 times a week to ship goods to my clients, and each time I get given the same specs " I've emailed them and the parcel is on the way to the correct Postnet in the vaal"!

This is now lead to my client posting my 2nd hand shop on the ******** group on social media.. While the useless members of the Postnet Brentwood park still have not fixed their mess.