0,20 nozzle is a new level of headache

Thanks to all the guys who are sharing their results and research here, you have inspired me to take this path too.

I know that almost everyone here uses the Bambulab A1. Unfortunately, I only have a bowden printer with a few years, which I have always used with the 0.40 nozzle, and I know how to solve my problems. Now I've changed to 0.20, and chaos has taken possession of my printer.

I've been trying to print for days, but most of the prints have the head moving but no filament comes out of the nozzle, the extruder motor is completely still. Other times some layers are printed and then the extruder stops. If I put the needle in the nozzle, the filament comes out but then it locks again.

I'm trying everything, but I really can't get over with it. Is anyone more experienced than me with such small nozzles?