User Comment: I tried to load and unload the filament but with no success. It seems something about the mechanism that is supposed to pull the filament is broken.
*See a video here.
PB Response: In my experience, this is caused by the screw that holds extruder arm being too tight. Use your 2.5mm hex wrench to loosen the screw just slightly. I think you will find that the drive gears will spin more freely.
Hope that is helpful,
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