I tried several things to fix it, but nothing worked:
Removing and re-placing the storage chests
Removing and re-placing the roboports
After some time they run out of energy, go back to the roboports to recharge, and then stay stuck hovering above the roboports with the items still in their inventory. They never finish the job or deliver anything.
- Reproduction Steps:
Go to Gleba for the first time in a new save.
Place roboports + storage chests.
Use a deconstruction planner on terrain/buildings.
Robots pick up items, then remain idle at the pickup location instead of delivering.

