Need Advice: Carbon fiber print problem

Hi, everyone!

This is my problem: When the printer starts printing it stop extruding. The filament stops. But it´s not due to obstruction or because the extruder has stopped.

I have already tried this:
- Clear the extruder and the nozzle
- Reduce printing speed (to 54 mm/s)
- Check that there´s no nozzle obstruction
- Adjust bed leveling and Z-set
- Adjust the extruder screw
- Check that the extruder isn´t worn
- Adjust the temperature (220°C)

What else can I do? Please... Help!!

Thanks Thanks Thanks


NOTE: I am using a Dowell 3D printer with a stainless steel nozzle (1.6) and I am new