Extruder K1 Max stopt extruding no Filament in the nozzle

Hello Everyone,

I have had the Creality K1 Max for 1 year now and I am very satisfied with it, but last week the filament got stuck in the cooling block and the nozzle so I had to disassemble everything from the nozzle to the extruder.
When I had everything loose and cleaned it again, and put it back together, I started printing again, the first object went well and with the second object I got the same problem again, the filament was completely stuck again.
What I am wondering now is, what is defective now, the extruder or the cooler on the printed circuit board - or the cooling block or the motor of the extruder.
When I wanted to print the second object, the extruder made a strange sound, and the first layer that came on the bed went well, but after 5 minutes no more filament came out of the nozzle.
Can someone tell me more where I should look for what is not working properly in the toolhead of the Creality K1 Max.

Kind regards
Wiebe