Undelivered parcels / returned to sender

Two parcels that I bought from overseas they did not get to my local post office when I looked on tracking history, they all get stuck at jhb international hub and then get returned back to the sender. I reali paid a lot for this parcels to not get to me and then be returned without getting to me first. Am really disappointed by post office unprofessionalism and even at Carletonville local post office I did not get assistance when I ask why is this happening. SYCN*** and VR***YP