I'm having this issue too making my Let's Play Series I was about to publish worthless sadly.
After updating ver.0.52, it was fatal to surround the area with "wall" of the "decorative" tab.
If there is a "connected wall" on the movement route, if there is a mass which becomes a gap of the wall, it goes to the destination through that mass.
When the bot moved, if there was "a mass without a wall" functioning as an entrance or exit, it could move inside and out of that area.
Was the condition for executing the detour operation more stringent by updating?
Regardless of the working point or return point, if there are long walls, the bots collide and stop moving.
If you click on it and look it up, the status will be shown as idle.
Some bots are working, but the green line indicating the destination is moving quickly. (I believe this is re-searching the destination)
"Wall" says to organize colonies and guide the traffic of the bot, as explained, but this does not help anything.
However, other buildings are avoided and moved.
Because the destination is in the screen, is it not it?
Is it impossible to use walls?
I have the same problem and because of those vehicles, I can't get anymore aluminum :/.