Check the .gcode file
Check that the .stl file does not presents 3d modeling issue (manifold edges / open surfaces)
Check if the parameters of the slicing software are correct Ex: nozzle diameter, filament diameter, % material flow, extrusion temperature, E-step/per mm.
Check if the extruder is working
1) Make sure that the RJ45 cable is properly connected to the extruder.
If it is not, turn the printer off and then connect the cable.
2) Check that the flexible pipes connecting the filament driver and the extruder are connected tightly, and that there are no obstructions or dirt.
3) Ensure that the filament has arrived to the melting zone inside the nozzle.
Check the leveling of the printing plate.
If the nozzle is too close to the printing plate the filament will struggle to get out, causing a blockage of the filament driver motor and the filament pushing gear.
Next, proceed with manual leveling procedure and clean the toothed gear to remove the any dust from between the teeth.
1) Check the printing bed leveling and:
menu > prepare > manual leveling > position > 00 > 01 > 02 > 03 > 00
Calibrate a distance of about 0.1mm between the tip of the nozzle and the glass plate.
2) Make sure that the power cable is well connected.
If not, turn the printer is off and reconnect it.
3) Make sure the control is active, then: menu > prepare > movement > 1mm > extruder
4) Check that the black knob on the threaded gear is well-connected to the motor shaft. To check this, hold the lever of the filament driver and try to pull the knob.
Then tighten the M3 set screw on the flat surface of the motor shaft, while centering the toothed part with the filament passageway.
5) Check if the cooling fan placed under the filament driver motor is working.
6) clean the extruder
If it still is not working, contact the customer service.