Menu is invisible in admin panel but it’s visible in front-end [closed]

I am not able to see any menus I added in my website back-end and even I am not able to create a new menu. Though the menu I created earlier is showing.

Please guide me on how I can make it visible so that I can add new pages in main menu. Let me know where I can share my website so that you can help me out. I look forward to hearing from you.

Thanks!

Here is the back end

Here is the front end

If you created the theme yourself, you should take a look at the WordPress Codex. They have a section called Navigation Menus. It contains all information you need about registering your menus the right way, so they are customizable.

To Keep things short:

Add this code to your theme’s functions.php to register your menu:

function register_my_menu() {
  register_nav_menu('header-menu',__( 'Header Menu' ));
}
add_action( 'init', 'register_my_menu' );

Then place this in your theme at the place your menu needs to be:

<?php wp_nav_menu( array( 'theme_location' => 'header-menu' ) ); ?>

Change names where needed.

If did not create the theme yourself. Then ask the theme author to implement the menu in the right way.

You can also create a Child Theme and edit the (purchased) theme yourself. Then create two files. The first file should be functions.php and add the above code to it. Then duplicate the theme file where the menu is located (probably header.php). And change the menu code to the code above.