Filament run out in slot3 during print, remaining filament was flushed, print stopped and printer turned off. Next day while sending another print, printer shown a message it cannot unload the old filament, even though there was supposed to be none, slot3 was empty, and a large blob of filament already flushed. Also printer shown a message that Slot1 filament has run out even though there was filament in the slot, on the AMS image on printer display and Bambu studio, and LED in AMS was turned on. Turned out that after the purge when filament run out, 13cm piece of running out filament was cut off and ejected back into the bowden tube as there are extruder gear marks on its end. So what appears to be, printer incompletely flushed the old filament, and most likely just cut it off and ejected back into bowden tube when trying to unload this small piece instead of just flushing it completely. X1C FW version 01.04.01.00 Don’t know how to check AMS FW version but it updated about 10 days ago, so should be the latest.