I fiddle with red flag to deposit Passengers from nearby small town to New Orleans to haul them to Los Angeles in Bridging a Nation mission.

But when I do the same to Lumber ,it's not deposit the extra to my town at all.
I threw 12 loads of lumber to a small town ,but there's just no lumber left.

Does it only work on Passengers ,Foods and Goods?

Alright ,I figured out why this happened to me. Must deposit in a station without the deposit cargo name in demand list at all. Demand 0 is still a demand.