Delays on deliveries

I would like to report poor customer service from SA Post office, I asked my cousin to courier a parcel from Durban to Mthatha on the 21 July 2020, I paid R110 for overnight courier (speed courier service) and they advised that we are going to get it on Thursday but till today I have not received it. When I call the call center no one is answering even the Bishopsgate post office where we posted from they don’t answer their phone or answer their emails. I want to know what’s happening as I cannot wait any longer I can’t pay so much for poor service.