That has been there for a while. I think as a result of porting it into tsw3. When it will be fixed, we don't know but dtg know the issue since many people have reported it
Some other trains are having that problem too. Seen it on the 422, 423 and ICE3 already. I guess it is something with unloading and loading in the trains. And then something goes wrong and they the model dissapears...