EventTrigger.OnUpdateSelected not working on mobile

as the titles says its not working on mobile but works on pc. unity answers is dead and have been waiting on a answer for 2 weeks. why does this not work on mobile. what im trying to achieve is when you press and hold on a button it shrinks or grows an object. it works fine on pc. the pressed and released functions work just now the grow/shrink on mobile2609515--182957--Capture.PNG

function Shrink(){
    if(obj != null && pressed == true)
    obj.transform.localScale -= Vector3.one * speed * Time.deltaTime;
}
function Grow(){
    if(obj != null && pressed == true)
    obj.transform.localScale += Vector3.one * speed * Time.deltaTime;
}

function Pressed(){
    pressed = true;
}
function Released(){
    pressed = false;
}

also why is unity answers dead?

which “mobile”? they all work differently…

android