WordPress loop issue getting links from custom taxonomy structure in navigation

Question

I am trying to create a dynamic loop to get the custom taxonomy categories to show in the navigation. I have registered my custom post type "services" with this code:

<?php 
function asb_post_types(){
    register_post_type('services', array(
        // remove editor so it takes away default content field
        'supports' => array ('title','excerpt', 'editor', 'thumbnail'),
        'rewrite' => array(
            // CHANGES ARCHIVE LINK
            'slug' => 'services'
        ),
        // create the archive for events
        'has_archive' => true,
        // makes visible to editors & previews of the site
        'public' => true,
        // tell it what icon to use
        'menu_icon' =>  'dashicons-admin-appearance',
        'taxonomies' => array('post_tag'),
        'labels' => array(
            // display name for admin panel
            'name' => 'Services',
            'add_new_item' => 'Add New Service',
            'edit_item' => "Edit Services",
            'all_items' => "All Services",
            'singular_name' => "service"
        )
    ));

}   

add_action('init', 'asb_post_types');
?>

In my functions.php I registered the custom taxonomy with the following code:

 function service_category_taxonomy() {
 
 
  $labels = array(
    'name' => _x( 'Service Category', 'taxonomy general name' ),
    'singular_name' => _x( 'service category', 'taxonomy singular name' ),
    'search_items' =>  __( 'Search Service Categories' ),
    'all_items' => __( 'All Service Categories' ),
    'parent_item' => __( 'Parent Service Categories' ),
    'parent_item_colon' => __( 'Parent Service Category:' ),
    'edit_item' => __( 'Edit Service Categories' ), 
    'update_item' => __( 'Update Service Categories' ),
    'add_new_item' => __( 'Add New Service Category' ),
    'new_item_name' => __( 'New Service Categories Name' ),
    'menu_name' => __( 'Service Category' ),
  );    
 
// Now register the taxonomy
  register_taxonomy('service categories',array('services'), array(
    'hierarchical' => true,
    'labels' => $labels,
    'show_ui' => true,
    'show_in_rest' => true,
    'show_admin_column' => true,
    'query_var' => true,
    'public'   => true,
    'exclude_from_search' => false,
    'rewrite' => array( 'slug' => 'service_category' ),
  ));
 
}

add_action( 'init', 'service_category_taxonomy', 0 );

In my navigation, I am using this loop to call the specific categories from the taxonomy:

<?php 
            $terms = get_terms(
              array(
                  'taxonomy'   => 'service categories',
                  'hide_empty' => true,
              )
          );

          // Check if any term exists
          if ( ! empty( $terms ) && is_array( $terms ) ) {
              // add links for each category
              foreach ( $terms as $term ) { ?>
                <li class="nav-item">
                  <a class="nav-link" href="<?php echo esc_url( get_term_link( $term ) ) ?>">
                      <?php echo $term->name; ?>
                  </a>
                </li>
              <?php
              }
          }
          ?>

I have flushed my permalinks, and when I hover my mouse over the links it generates a URL that should work, but when you click on it, it just refreshes the front-page.php template. My blog archive and index pages work properly for the blog so I am kind of at a loss why only this is not functioning as expected. Any help is appreciated.

Answer 1

After doing some research the WordPress only allows lowercase letters, dash, and underscore for the custom taxonomy name. I changed it to a new name and it worked perfectly. Hopefully, this helps someone in the future!