How to Restrict Variables in Selection Screen

Hi Experts,

I have set filter variable for my Region which includes (East, West, North, South).

And I'm restricting North and South in the Selection Screen and displaying a choice of East or West on the Selection Screen.

I tried right click variable in filter pane-> Restrict -> Move.....East and West to right side. and saved it.

When I tried executing it I'm being displayed all the 4 values at the Selection Screen.

Can any real experts help me resolve this

Thanks