Rewrite WordPress Custom URL

WordPress has its own system managing redirects and page routes, you don’t need to edit the .htaccess file. You’ll want to start with the function add_rewrite_rule().

It takes 3 arguments:

1. route (as regex)
2. query vars
3. priority

So first, you need to find out the query vars of account/customer-bookings/. If it is a page, it can be page_id. To reproduce what WordPress already does, it could be (XXX being the specific page_id):

add_rewrite_rule(
    '^account/customer-bookings/?$',
    'index.php?page_id=XXX'
);

Now you just need to expand this: (don’t forget to flush rewrite rules after adding this code!)

add_action('init', 'wpse_view_booking_rewrite');
function wpse_view_booking_rewrite() {
    add_rewrite_rule(
        '^account/customer-bookings/view-booking/([^/]+)/?$',
        'index.php?page_id=XXX&view-booking=$matches[1]',
        'top'
    );
}

This should already present the correct page. However, you won’t be able to use get_query_var('view-booking'), because it is no default variable. To solve this, simply tell WP to watch out for it like so

add_filter('query_vars', 'wpse_view_bookings_filter');
function wpse_view_bookings_filter($vars) {
    $vars[] = 'view-booking';
    return $vars;
}

At this point WordPress knows about the variable, and by calling get_query_var('view-booking') you will get the proper variable.