Header Suddenly pop and disturb the whole page

[Aunix]

so the issue is

when i scroll header doesn't move and as soon as it disappear it pops on the top of the screen and disturb the whole page

i want it to either stick at the top of the screen all the time or disappear when scrolling down and reappear when scrolling up

i am very new to shopify so do not know which file is resposible for controlling header, i attached header-css.liquid if you need any other file please tl

{{ 'bootstrap.min.css' | asset_url | stylesheet_tag }}

{% if content_for_layout or content_for_header contains 'sli' %}
{{ 'icons.min.css' | asset_url | stylesheet_tag }}
{% endif %}

{% if content_for_layout or content_for_header contains 'icofont' %}
{{ 'icofont.min.css' | asset_url | stylesheet_tag }}
{% endif %}


{% if content_for_layout contains 'animated' %}
{{ 'animate.css' | asset_url | stylesheet_tag }}
{% endif %}

{% if content_for_layout contains 'magni_video_pop' or content_for_layout contains 'img-popup' %}
{{ 'magnific-popup.css' | asset_url | stylesheet_tag }}
{% endif %}

{% if content_for_layout contains 'owl-carousel' %}
{{ 'owl-carousel.css' | asset_url | stylesheet_tag }}
{% endif %}

{% if content_for_layout contains 'common_slick_slider' %}
{{ 'slick-slider.css' | asset_url | stylesheet_tag }}
{% endif %}


{{ 'plugins.css' | asset_url | stylesheet_tag }}
{{ 'style.css' | asset_url | stylesheet_tag }}

<!-- Theme Default CSS -->
{{ 'theme-default.css' | asset_url | stylesheet_tag }}
<!-- Make your theme CSS calls here -->
{{ 'theme-custom.css' | asset_url | stylesheet_tag }}

{% if settings.rtl_enable %}
{{ 'theme-rtl.css' | asset_url | stylesheet_tag }}
{% endif %}

{{ 'theme-responsive.css' | asset_url | stylesheet_tag }}
{{ 'skin-and-color.css' | asset_url | stylesheet_tag }}

{%- if settings.theme_custom_css_style != '' -%}
	{{ settings.theme_custom_css_style }}
{%- endif -%}

[Aunix]

The Problem is with the whole store, only home screen kinda better and its only when i have that slider on top if i hide it, same problem occur on home screen as well

https://www.aunixbrand.store/collections/earbuds

https://aunixbrand.store/

[Aunix]

yeah this will do

[Aunix]

well i tired there is no option for that