Jemand gab mir das und stieg aus dem Zug. Was soll ich damit machen???

Nothing. It’s a common beggar scam. Don’t touch it, don’t make eye contact and they’ll just take the item/sign back.

Free labubu

Thank them for being one of the millions of people in Germany who think people like recycling their pointless printed PSA stuff.

It is a common beggar scam. Similar scams can be seen in most if not all major european cities. For example Rome and the wristlet scam, Florence and the rose sellers etc. They try to sell you a traumatic story about being disabled, kids in need and they just try to get a little money by selling random junk. But it is usually an organised group working in pairs that try to get cash from unsuspecting people by making them feel guilty or they can get aggressive and threaten you verbally (and even physically) to pay. Be advised quite often they use the distraction so others in the group can pick pockets.

If it happens to you: Do not touch the object they hand you, do not interact with the person, keep an eye on all your valued possessions and most certainly do not give them any money!

In this case most likely they got spooked. A member of the group probably spotted either a train conductor, police officer or any other authority and they decided to make a run for it at the next station.

Scam. Ignore it.

Well, now its your job to keep the legacy going. 

Since you have his Documentation, dont shower, out on some sunglasses and start handing these out.

Free money