The tokens of faulty items shouldn't continue in the flow, since those items are sorted into a different rack and stay there. It can happen that two tokens get assigned the same tote, if a second tote is generated (and thus a pair of tote and item completed) before the previous one has left the combiner. This then leads to the error, because the tote won't exist anymore when the second of those tokens tries to move it out of the rack. To prevent this, you could simply wait for an item to exit Queue8 before letting the token continue.
The Wait for Event activities in the activity blocks that move the totes in and out of the racks currently just serve as delays. The tokens have to acquire the ASRS as a resource, so only a single tokens can be present at a time and thus the event of another token exiting the Run Sub Flow can not happen.
robotpickandinspect-26.fsm
