Get alll customer mobile phone numbers in Woocommerce

I want to loop all the phone numbers of my users into an input field. So far, I'm not getting any luck with the following:

<?php for get_user_meta('phone_number',true); { echo $phone; "," } ?>

I'm trying to list them as 07812345678, 07812345678, 07812345678, etc... until the last number where there is no "," following it. Can someone help me? This is executed on the homepage of the admin dashboard if that makes any difference...

You can use this custom shortcode that uses a very light sql query to get all "customer" user role "billing phone" numbers as a coma separated string of number phones

If you are using a custom phone number custom field, you just need to replace in the function billing_phone by your custom field slug (as phone_number for example)

add_shortcode( 'customers_phones', 'get_customers_phone' );
function get_customers_phone(){
    global $wpdb;

    $results = $wpdb->get_col( "
        SELECT DISTINCT um.meta_value FROM {$wpdb->prefix}users as u
        INNER JOIN {$wpdb->prefix}usermeta as um ON um.user_id = u.ID
        INNER JOIN {$wpdb->prefix}usermeta as um2 ON um2.user_id = u.ID
        WHERE um.meta_key LIKE 'billing_phone' AND um.meta_value != ''
        AND um2.meta_key LIKE 'wp_capabilities' AND um2.meta_value NOT LIKE '%administrator%'
    " );

    // return a coma separated string of "customer" billing phones numbers
    return implode( ', ', $results );
}

Code goes in function.php file of your active child theme (or active theme). Tested and works.

USAGE - Displaying the number phones coma separated string:

1. In any Wordpress post or page text editor that accepts shortcodes:

   [customers_phones]
   

2. Inside php code

   echo do_shortcode("[customers_phones]");
   

3. Inside html code in a php file

   <?php echo do_shortcode("[customers_phones]"); ?>
   

---

Here below a replacement version without targeting "customer" user role:

add_shortcode( 'customers_phones', 'get_customers_phone' );
function get_customers_phone(){
    global $wpdb;

    $results = $wpdb->get_col( "
        SELECT DISTINCT um.meta_value FROM {$wpdb->prefix}users as u
        INNER JOIN {$wpdb->prefix}usermeta as um ON um.user_id = u.ID
        WHERE um.meta_key LIKE 'billing_phone' AND um.meta_value != ''
    " );

    // return a coma separated string of "customer" billing phones numbers
    return implode( ', ', $results ); 
}