Hope it works, Bettina! When I ordered something htat used DHL they told me it would go there so I wonder if your Mum has any more details ? However, if you have the tracking number and that doesn’t work, I can’t think what else to do 
We have had problems with parcels from Munich taking a long time, but the last one arrived in good time.
It works well when I post to Germany. Usually takes 3-4 days to arrive. Mom likes her little cheese crackers and french honey so a parcel leaves on average every 6 weeks.
Usually our post is quite good, but since Christmas the German deliveries have run into problems. I’ll check with the distribution office - maybe they can shed some light.
Our German deliveries have arrived as normal.