Ender-3 V2 Neo doesn't start to print

Hi,

I have some issues with my Ender 3 V2 neo not starting to print anymore. I had to swap the hotend-kit and now it heats up, it moves, it correctly determines it current position, yet it just wont start the print and just remains in position for hours.
I am a little irritated, that the z-axis-limit port on the board is empty, but I don’t recall that it was used before and as far as I can see, there is no direct limiter switch for z-axis on this particular model.
Anyone had similar issues before or got any idea how to solve? I don’t want to buy a new printer (though I am not that hard against getting a bigger one :D).

Cheers!