Filament cannot be extruded during printing.

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  1. Make sure filament is deeply inserted into the correct hole on top of the extruder.
  2. If filament is tangled, untangle it.
  3. Make sure the printing temperature is correct. (usually between 210-220 Celsius degree)
  4. Try to clean the congested nozzle: heat up the nozzle and pull out filament, then insert a thin iron bar into the filament hole on top of the extruder harder to squeeze the residue out of nozzle.
  5. Contact for technical support.