Html tags disappearing after clicking save

.submenu { padding: 10px 0 0; margin: 0 auto; text-align: center; font-size: 18px; text-weight: bold; }
.submenu .wpb_column { border-bottom: 1px solid #DDD; }
.submenu ul { list-style: none; padding: 0 !important; }
.submenu ul li { display: inline-block; position: relative; }
.submenu ul li a { 
    text-decoration: none; padding: 10px 50px; border: 0 !important;
}
.myList{ list-style-type: none;}
.submenu ul li a:hover {
    text-decoration: none !important;
}
.stick {
    position:fixed;
    top:0;
    width:100%;
    z-index:100;
    background-color:#F7F7F7;
}

function sticky_relocate() {
  if(jQuery('#submenu-anchor').length > 0) {
    var window_top = jQuery(window).scrollTop();
    var div_top = jQuery('#submenu-anchor').offset().top;
    if (window_top > div_top) {
        jQuery('.submenu').addClass('stick');
        jQuery('#submenu-anchor').height(jQuery('.submenu').outerHeight());
    } else {
        jQuery('.submenu').removeClass('stick');
        jQuery('#submenu-anchor').height(0);
    }
  }
}

jQuery(function() {
    jQuery(window).scroll(sticky_relocate);
    sticky_relocate();
});

This problem occured before but it was okay after adding the tags. Why is this happening?
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