Scrollable Container cant swipe upward totally

[jovel6]

hi all i used scrollable container effects of uitoolkit, was able to swipe downward, but swiping upward is working but cant totally swipe upward. its like when you point your mouse upward the images bounce downward.

heres my code:

    var scrollable = new UIScrollableVerticalLayout(10);
    scrollable.alignMode = UIAbstractContainer.UIContainerAlignMode.Center;
    scrollable.position = new Vector3( 0, 0, 0 );
    var width = UI.scaleFactor * 800;
    scrollable.setSize( width, Screen.height / 0.4f );