Deutsche post tossing my iPad away - any advice?

Hi,

I recently ordered an ipad from Amazon from a Germany seller.

I returned the ipad and shipped it to Germany from Singapore.

I got the status that the item couldn’t be delivered, and the parcel was routed to Deutsche Post. so I sucked it up and I’ll deal with the ipad myself.

However, i found out when I got my parcel today that the ipad box had been opened, and the ipad was missing. In the box I got a note from Deutsche Post.

God, I’m at a loss at what to do. Anyone could give advice / have such similar experience with Deutsche post?