Particlesystem: "Pick random" from collection - doesnt work for new objects!

I had following problem,
while duplicating objects, it did not change the emitted particle, even so i attached it with a particlesystem with “pick random” from collection.

Setup:

  • Collection “candles”* with different candles.
  • “Candle holder Mesh” with particlesystem → render as collection (*“candles”) → checked Pick random

So what did i do wrong? Why hasnt my duplicated object a different "candle"particle on top? Even random size is ignored! Is there a work around?

Thank you!

edit: Change the Seed value at the particle system, under the emission - number field