Solved Parallax effect acting weird on mobile

Hi
I used a parallax effect fot the header of the site, and it's working weird on mobile: On mobile I see both the image fixed to the background (like there is no parallax) and at the same time the same image doing the parallax effect (open on mobile www.cmtmusical.com and look at the homapage).
This is what I did:
Divi > Theme Settings > Integration, then Add code to the < head > of your blog I put this code

<script>
jQuery(document).ready(function($) {
// Mobile device check
$is_mobile_device = null !== navigator.userAgent.match(/Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/);
if ($is_mobile_device) {
// Function to check if an element is in the Viewport
isInViewport = function(elem) {
elementTop = elem.offset().top, elementBottom = elementTop + elem.outerHeight(), viewportTop = $(window).scrollTop(), viewportBottom = viewportTop + $(window).height();
return elementBottom > viewportTop && elementTop < viewportBottom;
};
// Apply Parallax transform calculations when scrolling
$(window).scroll(function() {
$(".et_parallax_bg").each(function() {
var $this_parent = $(this).parent();
// Check if the parent element is on-screen
var $is_visible = isInViewport($this_parent);
if ($is_visible) {
element_top = $this_parent.offset().top,
parallaxHeight = $(this).parent(".et_pb_fullscreen").length && $(window).height() > $this_parent.innerHeight() ? $(window).height() : $this_parent.innerHeight(),
bg_height = .3 * $(window).height() + parallaxHeight,
main_position = "translate(0, " + .3 * ($(window).scrollTop() + $(window).height() - element_top) + "px)";
$(this).css({height: bg_height,"-webkit-transform": main_position,"-moz-transform": main_position,"-ms-transform": main_position,transform: main_position});
}
});
});
}
});
</script>

then, both in section settings and full width header setting:
CSS Class: dtb-mobile-parallax
Background > Parallax effect: yes > CSS

What I did wrong?

 

So after the other long code, in the "head" section? It's not working :/

 

It works! Thanks!