Check that the feeding gear on the extruder is properly engaged on the filament.
I had this issue and it turned out the pivot point on the extruder had gotten sticky, so the spring wasn't compressing the gear onto filament enough to reliably grab it.
Check that the feeding gear on the extruder is properly engaged on the filament.
I had this issue and it turned out the pivot point on the extruder had gotten sticky, so the spring wasn't compressing the gear onto filament enough to reliably grab it.