Appalling Customer Service in Century City Postnet

I am really not impressed with the service I have received from Postnet Century City. I sent this package off on the 29th of May 2020 for my client in Cape Town. I did a postnet to postnet delivery and this was meant to be delivered to one of these branches. The parcel was then received by Marc in Century City, which was confirmed by Pombla who works in your Linkhill branch in Waterfall KZN. As she called them to check where the parcel was on the 19th June 2020. I then emailed them today and called to see if they received the email. Marc himself answered the call and we had a chat. He could hear in my tone of voice I was frustrated and annoyed that my parcel was not where they had originally sent it as my client went to collect it and it wasn't there, but rather at another branch a million miles away from my client. This is an inconvenience for my client and I was trying to rectify the situation. I asked Marc for a date as to when this would be rectified and when my client could come collect the parcel. I got a lovely "I don't know" great customer service of course. I started getting more annoyed as he had no solution to the problem. I asked him for the parcel to be brought to the correct postnet and he told me it would cost me. I of course have already paid for it to go to Century City so I said no I won't pay more because of Postnet's mistake. I was talking to him and awaited an answer only to hear him talking to someone in the background so he just left me talking on the phone. I then said Marc and of course no answer. I was shocked at what I was hearing and the lack of customer service and appalled he just put the receiver next to the phone and carried on like no one was on the phone. Then I said what is wrong with you to do that and he put the phone down. So still my inquiry has not been resolved. Still I don't have an answer for my client who was meant to receive their parcel over a month ago. Please can someone help me in this matter.