I have an issue on redirecting the user to sign-in URL. When they click the "post comment" button, it should check first if the user is logged in to continue, and if not they are suppose to redirect on sign-in URL.
I add this code to functions.php file: using "wpdiscuz_before_comment_post" hook.
add_action("wpdiscuz_before_comment_post", function () {
  if ( ! is_user_logged_in() ) {
    wp_safe_redirect( 'https://vinhammer.com/sign-in/' );
    exit;
  }
});
but when I click the "Post Comment" button it doesn't redirect to sign-in page, instead the page shows inside a pop-out error message.

