Need help with this unknown part in my stick!

Hi guys! i watched a few videos on youtube on how to tighten the spring in an arcade stick so i thought i would try that out myself on my SFxTekken MCZ stick.
However, theres this missing part (White plastic blocker) and i dont know where it comes from!! Can anyone help?



Also after assembling everything without this white color piece, my joystick is unable to make any physical connections to the sensors that input the directions (those clickers).

Any help would be greatly appreciated!