No service S.A. Post

My daugther has posted 5 different items to me from germany, one a Registered letter, since April 2018. Only one item arrived at our local Post Office, ripped open and things missing. Regarding the 4 missing parcels, we found out via tracking numbers, that all had arrived in S.A. and then gone missing. The german postal service has made contact with the S.A. Post and enquired about the missing parcels, but S.A. Post does not react. From my local Post Office I got a Telefon number to call, but calls are not answered at any given times. What options do I have to get any results?