Help with face masks changing with tap script

I'm trying to use a script (shown below) for switching through multiple face masks when the user taps the screen. 

The problem is only the first face mask is aligned to the face, the rest are not.

Is there a way around this issue?

//@input Component.FaceMaskVisual visual
//@input Asset.Texture[] postEffects
var count = 0;
function onTapped(eventData)
{
script.visual.mainPass.baseTex = script.postEffects[count]

if(count < script.postEffects.length - 1){
count++
} else
{
count = 0
}
}

var event = script.createEvent("TapEvent");
event.bind(onTapped);