Hello AmeliaFLYgurl,

the production warehouse can be emptied by building “carrier” near the buildings. The trucks drive to the factories and pick up the goods. :-)

I think someone skipped the tutorial... or forgot how to read. Production warehouse isnt important for you as the player, its a temp storage for the goods before being transported to your actual warehouse. If you havent built, as mentioned above, the logistical building, your resources arent going anywhere.