Undelivered Parcel

I have been waiting for a parcel from Singapore since 10/05/2019.

Local tracking number: RI ********** 96ZA International tracking number: RF ********** 37SG

On the South African Post Office website, when I track my parcel, it says that my parcel was delivered to Totiusdal Post Office on 10/05/2019 and then returned back to JHB INTL (Hub) on the same day?

The reason: Missed Delivery/Attempted delivery today

I have e-mailed ********** and ********** numerous times, just to receive an undelivered message. I have called ***numerous times as well, and there is never any answer on that number.

WHO CAN I CONTACT TO GET MY PARCEL?