Custom Taxonomy Creates Unwanted Integer Terms on Post Save

After I select terms and then save my custom post type, new taxonomy terms are generated with integer values and selected every time. I don’t know what the problem is, nor have I found any sort of the same issue anywhere on the internet. Here is a picture of what exactly is going on: http://prntscr.com/fvfqvf

Registering Post Type

function tbs_register_post_type() {
    $singular="Stylist";
    $plural="Stylists";

    $labels = array(
        'name' => $plural,
        'singular_name' => $singular,
        'add_new' => 'Add New',
        'add_new_item' => 'Add New ' . $singular,
        'edit_item' => 'Edit ' . $singular,
        'new_item' => 'New ' . $singular,
        'view_item' => 'View ' . $singular,
        'view_items' => 'View ' . $plural,
        'search_items' => 'Search ' . $plural,
        'not_found' => 'No ' . strtolower($plural) . ' found',
        'not_found_in_trash' => 'No ' . strtolower($plural) . ' found in trash',
        'all_items' => 'All ' . $plural,
        'archives' => $singular . ' Archives',
        'attributes' => $singular . ' Attributes',
        'insert_into_item' => 'Insert into ' . strtolower($singular),
        'uploaded_to_this_item' => 'Uploaded to this ' . strtolower($singular),
        'featured_image' => $singular . ' Picture',
        'set_featured_image' => 'Set ' . strtolower($singular) . ' picture',
        'remove_featured_image' => 'Remove ' . strtolower($singular) . ' picture',
        'use_featured_image' => 'Use as ' . strtolower($singular) . ' picture',
        'filter_items_list' => 'Filter ' . strtolower($plural) . ' list',
        'items_list_navigation' => $plural . ' list navigation',
        'items_list' => $plural . ' list'
    );

    $args = array(
        'label' => $plural,
        'labels' => $labels,
        'description' => 'A custom plugin to create, edit, and delete stylists made for -.',
        'public' => true,
        'menu_position' => '2',
        'menu_icon' => 'dashicons-groups',
        'supports' => array('title', 'thumbnail'),
        'taxonomies' => array('tbs_skills', 'tbs_fun_facts'),
        'has_archive' => false,
        'rewrite' => array('slug' => 'stylists')
    );

    register_post_type('tbs_stylists', $args);
}
add_action('init', 'tbs_register_post_type');

Registering Taxonomies

function tbs_register_skills_taxonomy() {
    $singular="Skill";
    $plural="Skills";

    $labels = array(
        'name' => $plural,
        'singular_name' => $singular,
        'all_items' => _('All '. $plural),
        'edit_item' => _('Edit ' . $singular),
        'view_item' => _('View ' . $singular),
        'update_item' => _('Update ' . $singular),
        'add_new_item' => _('Add New ' . $singular),
        'new_item_name' => _('New ' . $singular . ' Name'),
        'search_items' => _('Search ' . $plural),
        'popular_items' => _('Popular ' . $plural),
        'separate_items_with_commas' => _('Separate ' . strtolower($plural) . ' with commas'),
        'add_or_remove_items' => _('Add or remove ' . strtolower($plural)),
        'choose_from_most_used' => _('Choose from the most common ' . strtolower($plural)),
        'not_found' => _('No ' . strtolower($plural) . ' found.')
    );

    $args = array(
        'label' => $plural,
        'labels' => $labels,
        'description' => 'A custom taxonomy for the stylists custom post type made for -.',
        'public' => true
    );

    register_taxonomy('tbs_skills', 'tbs_stylists', $args);
}
add_action('init', 'tbs_register_skills_taxonomy');

function tbs_register_fun_facts_taxonomy() {
    $singular="Fun Fact";
    $plural="Fun Facts";

    $labels = array(
        'name' => $plural,
        'singular_name' => $singular,
        'all_items' => _('All '. $plural),
        'edit_item' => _('Edit ' . $singular),
        'view_item' => _('View ' . $singular),
        'update_item' => _('Update ' . $singular),
        'add_new_item' => _('Add New ' . $singular),
        'new_item_name' => _('New ' . $singular . ' Name'),
        'search_items' => _('Search ' . $plural),
        'popular_items' => _('Popular ' . $plural),
        'separate_items_with_commas' => _('Separate ' . strtolower($plural) . ' with commas'),
        'add_or_remove_items' => _('Add or remove ' . strtolower($plural)),
        'choose_from_most_used' => _('Choose from the most common ' . strtolower($plural)),
        'not_found' => _('No ' . strtolower($plural) . ' found.')
    );

    $args = array(
        'label' => $plural,
        'labels' => $labels,
        'description' => 'A custom taxonomy for the stylists custom post type made for -.',
        'public' => true
    );

    register_taxonomy('tbs_fun_facts', 'tbs_stylists', $args);
}
add_action('init', 'tbs_register_fun_facts_taxonomy');

Editing Post Page Functions

function tbs_change_title_text($title){
    $screen = get_current_screen();
    if ('tbs_stylists' == $screen->post_type) $title="Enter stylist name";
    return $title;
}
add_filter('enter_title_here', 'tbs_change_title_text');

function tbs_move_metas() {
    remove_meta_box('tagsdiv-tbs_skills', 'tbs_stylists', 'side');
    add_meta_box('tagsdiv-tbs_skills', 'Skills', 'post_categories_meta_box', 'tbs_stylists', 'normal', 'high', array('taxonomy' => 'tbs_skills'));

    remove_meta_box('tagsdiv-tbs_fun_facts', 'tbs_stylists', 'side');
    add_meta_box('tagsdiv-tbs_fun_facts', 'Fun Facts', 'post_categories_meta_box', 'tbs_stylists', 'normal', 'high', array('taxonomy' => 'tbs_fun_facts'));
}
add_action('admin_init', 'tbs_move_metas');

If anyone could offer some insight I would appreciate it. Thank you.

This appears to be a result of the conflict between declaring a non-hierarchical custom taxonomy, and using the post_categories_meta_box (checkboxes) as an interface.

You could call the discrepancy a bug in WP Core, certainly the fact that the conflict is allowed in the taxonomy declaration itself.

The problem seems to be that for your non-hierarchical taxonomy, the checkboxes are rendered with the input “value” = term_id, but the checkbox callback used at post save time stores the value of the checked item as a term name, so you get that integer (the ID) created and stored as a “new” term.

See also this question

Solution for now: just declare the taxonomy as hierarchical if you want to use the checkbox interface.