How to adjust headlight level?

[ProjectM96]

This is a 2000 Boxster. OEM headlights.

In the headlight I can see the white stick with the black line. It is a bit off when I compare it to my other headlight. And the light points upwards more than the other headlight.

I took my headlight out. Opened the cap in the back where I can access the light bulbs.

I saw the white plastic parts related to the light leveler. But I couldn't move it no matter what I tried. Is there a trick to this?

I already looked in owners manual. It was not helpful.