erikaN

Problem:
If you're experiencing issues where the language selector does not change the language on blog posts, and instead links to the current language rather than the selected alternate language, the issue might be with your theme's functions.php file.
Solution:
In this case, the issue was caused by a function inside the functions.php file of a Child Theme:

function change_blog_links($post_link, $id = 0)
{
 
    $post = get_post($id);
 
    if (is_object($post) && $post->post_type == 'post') {
        return home_url('/blog/' . $post->post_name . '/');
    }
 
    return $post_link;
}
add_filter('post_link', 'change_blog_links', 1, 3);
remove_action('wp_head', 'wp_resource_hints', 2);

This code modifies the blog post links and can interfere with the WPML language switcher. Removing this snippet should allow the language switcher to function correctly.

If this solution does not resolve your issue, or if it seems outdated or irrelevant to your case, we highly recommend checking related known issues, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. Additionally, you can open a new support ticket for further assistance at WPML support forum.