Removed custom post type archive page shows blog page

Question

On a website made with a purchased template, a custom post-type had an archive page. I didn't want that archive page, so I altered the custom post-type in a child-theme like so:

function remove_archive(){
    $portfolio = get_post_type_object( 'portfolio' );
    $portfolio->has_archive = FALSE;
    register_post_type( 'portfolio', $portfolio );
}
add_action( 'init', 'remove_archive', 20 );

This removed the custom post-type archive. However, it was my intention that the url /portfolio would be freed up for use for a page. But even after refreshing the permalinks, clearing caches etc. the url doesn't point to the page. Instead it points to the blog page, which hasn't been set in the settings at all.

The solution should be a situation in where /portfolio is a page, and /portfolio/* is the URL structure for the posts. However, at this moment, that is not working in any way.

Am I missing something?

Edit

As per Pieter's comment, I've added the template filter template_include:

function uncode_redirect_page($original_template) {
    global $is_redirect;
    $is_redirect_active = ot_get_option('_uncode_redirect');
    if ($is_redirect_active === 'on') {
        if(! is_user_logged_in() )
    {
        $is_redirect = true;
      return get_template_directory() . '/redirect-page.php';
    }
    }
    return $original_template;
}
add_filter('template_include', 'uncode_redirect_page');

Answer 1

If you are using WordPress 4.4+ (which you should), you can make use of the register_post_type_args filter to adjust the arguments passed to register_post_type() when the post type is registered. In your child theme, you can do the following

add_filter( 'register_post_type_args', function( $args, $post_type )
{
    // Make sure we only target the portfolio post type
    if ( 'portfolio' !== $post_type )
        return $args;

    /**
     * We are currently registering the portfolio post type, lets continue
     * For debugging purposes, you can do the following inside the filter
     * ?><pre><?php var_dump($args); ?></pre><?php
     *
     * Modify the arguments as needed
     */
    $args['has_archive'] = false;
    $args['rewrite']     = true;

    return $args;   
}, PHP_INT_MAX, 2);

Just remember to flush your rewrite rules after adding the filter. Make sure you adjust the filter to your needs. This should take care of the template load, you should see the page loaded which you created in the back end when you visit http://example.com/portfolio/ (if your created page has a slug of portfolio, ie a permalink structure of http://example.com/portfolio/).

If this does not work, you have something inside your theme which is causing this issue, more likely a pre_get_posts action which is suppose to target the portfolio post type page. You should also consider a bad rewrite as well

EDIT

The final issue was that the template_include filter as mentioned in the question was causing the issue. Removing the filter in the child theme and reflushing the permalinks solved the issue

Answer 2

The archive page is created according to the name of slug of post type so if you want to portfolio as simple page not the archive page just change the slug of portfolio post type. It will solve your problem.

$labels = array(
        'name'               => _x( 'Blog', 'post type general name', 'your-plugin-textdomain' ),
        'singular_name'      => _x( 'Blog', 'post type singular name', 'your-plugin-textdomain' ),
        'menu_name'          => _x( 'Blog', 'admin menu', 'your-plugin-textdomain' ),
        'name_admin_bar'     => _x( 'Blog', 'add new on admin bar', 'your-plugin-textdomain' ),
        'add_new'            => _x( 'Add New', 'Blog', 'your-plugin-textdomain' ),
        'add_new_item'       => __( 'Add New Blog', 'your-plugin-textdomain' ),
        'new_item'           => __( 'New Blog', 'your-plugin-textdomain' ),
        'edit_item'          => __( 'Edit Blog', 'your-plugin-textdomain' ),
        'view_item'          => __( 'View Blog', 'your-plugin-textdomain' ),
        'all_items'          => __( 'All Blog', 'your-plugin-textdomain' ),
        'search_items'       => __( 'Search Blog', 'your-plugin-textdomain' ),
        'parent_item_colon'  => __( 'Parent Blog:', 'your-plugin-textdomain' ),
        'not_found'          => __( 'No Blog found.', 'your-plugin-textdomain' ),
        'not_found_in_trash' => __( 'No Blog found in Trash.', 'your-plugin-textdomain' )
    );

    $args = array(
        'labels'             => $labels,
        'public'             => true,

        'publicly_queryable' => true,
        'show_ui'            => true,
        'show_in_menu'       => true,
        'query_var'          => true,
        'rewrite'            => array( 'slug' => 'test' ),
        'capability_type'    => 'post',
        'has_archive'        => true,
        'hierarchical'       => false,
        'menu_position'      => null,

        'supports'           => array( 'title', 'editor', 'author', 'thumbnail', 'excerpt',)
    );
    register_post_type( 'Blog', $args );