So i cant use PSP Left Analog Stick correctly

[Skinkers]

I dont know if it is supposed to be like that but, like in psp, you can move really slowly or move normaly with your left analog st. (and only analog st. since its a psp), but in ppsspp i can only move normally so... how do i explain it better...

So Im playing ''MGS PW'' and in the game you can either move slowly or fast, and i dont know how to move slowly or even configure it in the ppsspp mapping.
I use Fusa Gamepad v3 and i dont really know what to do, I've already search through alot of post and found nothing.

''Why dont you play in the psp instead?'' Because i know that if i play in the pc it would be more enjoyable.

Would appreciate if someone knew what to do.