Menus not seen in Look after being registered

The menus have been registered in capabilities.php, however they do not seem throughout the Look > Menus part in Admin and the pages, posts and so forth choices are greyed out.

The menus are saved, as you can’t create the menu with the identical identify once more.

Inside capabilities.php:

perform theme_setup() {
    add_theme_support( 'automatic-feed-links' );
    add_theme_support( 'post-thumbnails' );
    add_theme_support( 'html5', array( 'search-form' ) );
    /*** Register Menus */
    if (function_exists('register_nav_menus'))
    {
        register_nav_menus(
        array(
            'main-menu'         => __( 'Essential Menu', 'website' ),
            'footer-menu'       => __( 'Footer Menu', 'website' ),
            )
        );
    }
}
add_action('after_setup_theme', 'theme_setup');

Inside header.php

wp_nav_menu(
                array(
                    'menu'          => 'Essential Menu',
                    'container'     => '',
                    'depth'         => 1,
                    'theme_location' => 'main-menu',
                )
            );

Inside footer.php

wp_nav_menu(
                array(
                    'menu'          => 'Footer Menu',
                    'container'     => '',
                    'items_wrap'    => '',
                    'theme_location' => 'footer-menu'
                )
            );

The principle difficulty right here is that these menus exist and are rendering out on the positioning, however they appear to be hidden throughout the admin panel and if a brand new menu is created it by no means exhibits up.

Utilizing WordPress model 4.7 (Newest)

Plugins:

What could possibly be inflicting this?