Step 1: Take everything apart and clean it, you have to be able to look through the throat and the nozzle without obstacles.
Step 2: Remove the PTFE Tube from the pressure fitting and inspect the tube for damages/compressions and cut off the damaged part.
Step 3: Put everything together nice and tight and mount it on the axis without the fans and do not insert the PTFE tube.
Step 4: Heat up the nozzle to 230°C and when heated carefully retighten the nozzle, let it cool down after that.
Step 5: Insert the PTFE tube and push it all the way in until it doesn’t move anymore.
Step 6: Install the fans, level the bed and try printing.