WordPress Wrapping tag within another tag in Navigation Menu

I am trying to edit the navigation menu and trying wrap anchor tag over an div.I am trying to achieve the following result:

<div class="nav-drawer-top-links">
    <a class="nav-content-column vertical-content-center" href="https://localhost/test/portfolio/">

    <div class="nav-content-box">
        Portfolio
        <span class="sub">Whatever</span>
    </div>
 </a>
</div>

But the result I keep getting is the anchor tag repeating and one of it closing outside of the div. Another anchor tag is being printed inside the div. I keep getting this result:

<div class="nav-drawer-top-links">
    <a class="nav-content-column vertical-content-center" href="https://localhost/test/portfolio/"></a>

    <div class="nav-content-box">
        <a class="nav-content-column vertical-content-center" href="https://localhost/test/portfolio/">Portfolio<br>
        <span class="sub">Whatever</span></a>
    </div>
</div>

This the code in my header.php

<?php $walker = new Menu_With_Description; ?>
                <div class="nav-drawer-wrap">
                <?php
                    wp_nav_menu( array(

                        'theme_location'    => 'primary',
                        'container'         => 'div',
                        'container_class'   => 'nav-drawer-interior',
                        'menu_class'        => 'nav-drawer-top-links',
                        'items_wrap'      => '<div class="nav-drawer-top-links">%3$s</div>',
                        'walker'            => $walker

                    ) );
                ?>

The following is my code functions.php

class Menu_With_Description extends Walker_Nav_Menu {
function start_el(&$output, $item, $depth, $args) {
    global $wp_query;
    $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';

    $class_names = $value = '';

    $classes = empty( $item->classes ) ? array() : (array) $item->classes;

    $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item ) );
    $class_names = ' class="' . esc_attr( $class_names ) . '"';

    $attributes = ! empty( $item->attr_title ) ? ' title="' . esc_attr( $item->attr_title ) .'"' : '';
    $attributes .= ! empty( $item->target ) ? ' target="' . esc_attr( $item->target ) .'"' : '';
    $attributes .= ! empty( $item->xfn ) ? ' rel="' . esc_attr( $item->xfn ) .'"' : '';
    $attributes .= ! empty( $item->url ) ? ' href="' . esc_attr( $item->url ) .'"' : '';

    $item_output = $args->before;
    $item_output .= '<a'. $attributes .'class="nav-content-column vertical-content-center"><div class="nav-content-box">';
    $item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
    $item_output .= '<br /><span class="sub">' . $item->description . '</span>';
    $item_output .= '</a></div>';
    $item_output .= $args->after;

    $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
}