do_shortcode groups_join not working in hook

Hi!

I am trying to add subscriber users automatically to the same group of the contributor after subscriber users have been created, but do_shortcode in hook seems not working. Please help!!!

This is my code

add_action( 'user_register', array($this, 'create_user'), 10, 1 );

function create_user($user_id) {

global $wpdb;

	//Get current user group id from database
	
	$getValue = $wpdb->get_results("SELECT user_id , wp_groups_group.group_id, wp_groups_user_group.group_id, name  FROM  wp_groups_group, wp_groups_user_group WHERE wp_groups_group.group_id =  wp_groups_user_group.group_id");

	$currentUser = wp_get_current_user();
	$currentUserID = $currentUser->ID;
	$groupID = "";
	$groupName = "";
	foreach ($getValue as $key => $value) {
		if ($currentUserID == $value->user_id  && $value->group_id > 1) {
			$groupID = $value->group_id;
			$groupName = $value->name;

		}else{
		}
	}

	do_shortcode('[groups_join group="'.$groupName.'"]');

}