Hardware Analog stick doesn't go all the way (PC controller)

[EpikJimmer]

I know this is way out of place but I don't know where else I should write this.

I have a (very) cheap controller for pc where the left stick doesn't fully work when I go diagonally up. It only goes in the middle or something.
Here's how it works:

And here's how it should work.

It only works when I give pressure to it.

I have no idea what's going on.
And yes, the stick's physically fine.

Edit: Now the stick doesn't go up either:

 

[g00s3y]

It's worn out. You'll need to replace the stick, or get a new controller.