Unordered display of items after switching from desktop to mobile and vice versa

There is a problem in my JavaScript code that I have been struggling with for about 2 days.

jQuery(document).ready(function($) {
    function ClickArrowsSubMenu($menu) {
        if ( ! $menu.hasClass( 'clickarrowssubmenu' ) ) {
            return;
        }
        $menu.find('.menu-item-has-children > a').off('click').click(function(e) {
            var $this = $(this);
            var offset = $this.offset();
            var x = e.pageX - offset.left;
            var y = e.pageY - offset.top;
            var isParentLevel = $this.closest('ul').parent().is('nav');
            var clickOnAfter = false;
            if (window.innerWidth > 768) {
                if (isParentLevel) {
                    clickOnAfter = (x < 9) && (y > 8 && y < 15);
                } else {
                    clickOnAfter = (x > 8 && x < 20) && (y > 20 && y < 27);
                }
            } else {
                if ($this.closest('nav').hasClass('account')) {
                    if (isParentLevel) {
                        clickOnAfter = (x < 9) && (y > 13 && y < 20);
                    } else {
                        clickOnAfter = (x > 8 && x < 20) && (y > 20 && y < 27);
                    }
                } else {
                    clickOnAfter = (x > 7 && x < 20) && (y > 20 && y < 27);
                }
            }
            if (clickOnAfter) {
                e.preventDefault();
                var $parent = $this.parent();
                var $submenu = $parent.children('.sub-menu');
                $('nav.menu').not($menu).find('.menu-item-has-children.active').removeClass('active').children('.sub-menu').slideUp();
                $('nav.menu').not($menu).prev('.hamburger-menu.open').click();
                if ($parent.hasClass('active')) {
                    $parent.removeClass('active');
                    $submenu.slideUp().find('.menu-item-has-children').removeClass('active').children('.sub-menu').slideUp();
                } else {
                    $parent.siblings('.menu-item-has-children').removeClass('active').children('.sub-menu').slideUp().find('.menu-item-has-children').removeClass('active').children('.sub-menu').slideUp();
                    $parent.addClass('active');
                    $submenu.slideDown(function() {
                        $(this).removeAttr('style');
                        $submenu.data('current-page', 0);
                        showPage($submenu, 0);
                    });
                }
            }
        });
    }

    function HamburgerMenu($menu) {
        if ( ! $menu.hasClass( 'hamburgermenu' ) ) {
            return;
        }
        if ($menu.prev('.hamburger-menu').length === 0) {
            $('<div class="hamburger-menu"><i class="fas fa-bars"></i></div>').insertBefore($menu);
            $menu.prev('.hamburger-menu').click(function() {
                $('nav.menu').not($menu).find('.menu-item-has-children.active').removeClass('active').children('.sub-menu').slideUp();
                $('nav.menu.hamburgermenu').not($menu).prev('.hamburger-menu.open').click();
                if ($(this).hasClass('open')) {
                    $menu.slideUp(function() {
                        $(this).removeAttr('style');
                        $(this).removeClass('act');
                    });
                    $(this).removeClass('open').html('<i class="fas fa-bars"></i>');
                } else {
                    $menu.slideDown(function() {
                        $(this).removeAttr('style');
                        $(this).addClass('act');
                    });
                    $(this).addClass('open').html('<i class="fas fa-times"></i>');
                }
            });
        }
    }

    function showPage($subMenu, page) {
        var $items = $subMenu.children('li');
        var totalItems = $items.length;
        var itemsPerPage = 2;
        $items.each(function(index) {
            if (index >= page * itemsPerPage && index < (page + 1) * itemsPerPage) {
                $(this).addClass('activ');
            } else {
                $(this).removeClass('activ');
                if (!$(this).attr('class')) {
                    $(this).removeAttr('class');
                }
            }
        });
        if (page > 0) {
            $subMenu.addClass('has-previous');
        } else {
            $subMenu.removeClass('has-previous');
        }
        if ((page + 1) * itemsPerPage < totalItems) {
            $subMenu.addClass('has-next');
        } else {
            $subMenu.removeClass('has-next');
        }
    }

    function Paginations($menu) {
        if ( ! $menu.hasClass( 'paginations' ) ) {
            return;
        }
        $menu.find('ul ul.sub-menu').each(function() {
            var $subMenu = $(this);
            var currentPage = 0;
            $subMenu.data('current-page', currentPage);
            $subMenu.on('click', function(event) {
                var offsetTop = $subMenu.offset().top;
                var offsetLeft = $subMenu.offset().left;
                var offsetRight = offsetLeft + $subMenu.outerWidth();
                var offsetBottom = offsetTop + $subMenu.outerHeight();
                var clickY = event.pageY;
                var clickX = event.pageX;
                var hasPrevious = $subMenu.hasClass('has-previous');
                var hasNext = $subMenu.hasClass('has-next');
                var $visibleItems = $subMenu.children('li:visible');
                var displayedItems = $visibleItems.length;
                var page = $subMenu.data('current-page');
                if (displayedItems === 1) {
                    if (hasPrevious && hasNext) {
                        var upArrowClickTop = offsetTop + 14;
                        var upArrowClickBottom = offsetBottom - 95;
                        var downArrowClickTop = offsetTop + 95;
                        var downArrowClickBottom = offsetBottom - 14;
                        var ArrowClickRight = (offsetLeft + offsetRight) / 2 + 6;
                        var ArrowClickLeft = (offsetLeft + offsetRight) / 2 - 7;
                    } else if (hasPrevious && !hasNext) {
                        var upArrowClickTop = offsetTop + 14;
                        var upArrowClickBottom = offsetBottom - 62;
                        var ArrowClickRight = (offsetLeft + offsetRight) / 2 + 6;
                        var ArrowClickLeft = (offsetLeft + offsetRight) / 2 - 7;
                    } else if (!hasPrevious && hasNext) {
                        var downArrowClickTop = offsetTop + 62;
                        var downArrowClickBottom = offsetBottom - 14;
                        var ArrowClickRight = (offsetLeft + offsetRight) / 2 + 6;
                        var ArrowClickLeft = (offsetLeft + offsetRight) / 2 - 7;
                    } else {
                        var upArrowClickTop = 0;
                        var upArrowClickBottom = 0;
                        var downArrowClickTop = 0;
                        var downArrowClickBottom = 0;
                        var ArrowClickRight = 0;
                        var ArrowClickLeft = 0;
                    }
                } else if (displayedItems === 2) {
                    if (hasPrevious && hasNext) {
                        var upArrowClickTop = offsetTop + 14;
                        var upArrowClickBottom = offsetBottom - 142;
                        var downArrowClickTop = offsetTop + 142;
                        var downArrowClickBottom = offsetBottom - 14;
                        var ArrowClickRight = (offsetLeft + offsetRight) / 2 + 6;
                        var ArrowClickLeft = (offsetLeft + offsetRight) / 2 - 7;
                    } else if (hasPrevious && !hasNext) {
                        var upArrowClickTop = offsetTop + 14;
                        var upArrowClickBottom = offsetBottom - 109;
                        var ArrowClickRight = (offsetLeft + offsetRight) / 2 + 6;
                        var ArrowClickLeft = (offsetLeft + offsetRight) / 2 - 7;
                    } else if (!hasPrevious && hasNext) {
                        var downArrowClickTop = offsetTop + 109;
                        var downArrowClickBottom = offsetBottom - 14;
                        var ArrowClickRight = (offsetLeft + offsetRight) / 2 + 6;
                        var ArrowClickLeft = (offsetLeft + offsetRight) / 2 - 7;
                    } else {
                        var upArrowClickTop = 0;
                        var upArrowClickBottom = 0;
                        var downArrowClickTop = 0;
                        var downArrowClickBottom = 0;
                        var ArrowClickRight = 0;
                        var ArrowClickLeft = 0;
                    }
                }
                var withinUpArrowArea = (clickY >= upArrowClickTop && clickY <= upArrowClickBottom && (clickX >= ArrowClickLeft && clickX <= ArrowClickRight));
                var withinDownArrowArea = (clickY >= downArrowClickTop && clickY <= downArrowClickBottom && (clickX >= ArrowClickLeft && clickX <= ArrowClickRight));
                if (withinUpArrowArea) {
                    event.stopPropagation();
                    if (page > 0) {
                         page--;
                         $subMenu.data('current-page', page);
                         showPage($subMenu, page);
                    }
                } else if (withinDownArrowArea) {
                    event.stopPropagation();
                    if ((page + 1) * 2 < $subMenu.children('li').length) {
                        page++;
                        $subMenu.data('current-page', page);
                        showPage($subMenu, page);
                    }
                }
                if (withinUpArrowArea || withinDownArrowArea) {
                    $subMenu.find('.menu-item-has-children.active').removeClass('active').children('.sub-menu').slideUp();
                }
            });
            showPage($subMenu, 0);
        });
    }

    function ResetMenu($menu) {
        if (window.innerWidth > 768) {
            $menu.prev('.hamburger-menu').remove();
            $menu.removeAttr('style').show();
            $menu.find('.menu-item-has-children').removeClass('active').children('.sub-menu');
        } else {
            if ( $menu.hasClass( 'hamburgermenu' ) ) {
                HamburgerMenu($menu);
            }
            $menu.find('.menu-item-has-children').removeClass('active').children('.sub-menu');
        }
    }

    function checkWindowWidth() {
        $('nav.menu').each(function() {
            var $menu = $(this);
            var isLargeScreen = window.innerWidth > 768;
            var isCurrentlyLargeScreen = $menu.hasClass('large-screen');
            var isCurrentlySmallScreen = $menu.hasClass('small-screen');
            if (isLargeScreen) {
                if (!isCurrentlyLargeScreen) {
                    $menu.addClass('large-screen').removeClass('small-screen');
                    if ( $menu.hasClass( 'clickarrowssubmenu' ) ) {
                        ClickArrowsSubMenu($menu);
                    }
                    if ( $menu.hasClass( 'paginations' ) ) {
                        Paginations($menu);
                    }
                    ResetMenu($menu);
                }
            } else {
                if (!isCurrentlySmallScreen) {
                    $menu.addClass('small-screen').removeClass('large-screen');
                    if ( $menu.hasClass( 'hamburgermenu' ) ) {
                        HamburgerMenu($menu);
                    }
                    if ( $menu.hasClass( 'clickarrowssubmenu' ) ) {
                        ClickArrowsSubMenu($menu);
                    }
                    if ( $menu.hasClass( 'paginations' ) ) {
                        Paginations($menu);
                    }
                    ResetMenu($menu);
                }
            }
        });
    }

    checkWindowWidth();

    $(window).resize(checkWindowWidth);

    function serach() {
        $( '.search-icon' ).on( 'click', function() { $( '.search' ).css( 'display', 'flex' ).fadeIn(); } );
        $( '.times' ).on( 'click', function() { $( '.search' ).removeAttr( 'style' ).fadeOut(); } );
    }

    serach();

});
  1. If the width of the browser is greater than 768 pixels or less than
    768 pixels (without switching to each other): by opening and closing
    the hierarchy (level), items 1 and 2 are displayed first, and when
    using hierarchy pagination (Level) The next items are also displayed
    until the last item.
  2. If the width of the browser is greater than 768 pixels or less than 768 pixels (by switching to each other): By opening and closing the hierarchy (level), items 1 and 2 are displayed first, and when using hierarchy pagination (level) after item 1 and 2, item 3 and 4 are displayed in order, but after item 3 and 4, the display order of the items is messed up and items 9, 10 and … are displayed to give.

When I am in position #1, there is no problem. But when I’m in situation number 2, the display order of the items gets messed up, and when I see item 1 and 2, by clicking on the next page, it jumps to item 7 and 8 and it doesn’t display in that order.

I was really confused.