How I can get custom field’s current value?

The author of plugin help me with that. Thanks all.

global $post;
        $product_colors = get_the_terms( $post, 'product_color' );
        $saved_colors = get_option( 'nm_taxonomy_colors' );

        if(isset($product_colors) && is_array($product_colors)){
            foreach($product_colors as $color){
                $term_id = $color->term_id;

                $hex_code = $saved_colors[$term_id];

                echo $hex_code . '<br />';
            }
        }