As you can see in the video, I have 2 small pipes in the warehouse.
1st pipe I loaded at the truck, it counts from 2 to 1.
I switched to the trailer and the second small pipe is visible on the trailer.
When I pack them, the pipes switches to metall beams and my pipe is lost (video at 0:28).
Same happened to me with concerte block at the ware-/storehouse near the garage. I craft 2 blocks and the 2nd block changes to consumables (or something else - next cargo in the list of the warehouse) when I try to pack the block.