PHP script to execute cronjob: update bp members last activity status to current time based on role

Question

I'm using this php script that is supposed to update bp members last activity status to current time but I'm getting a HTTP 500 error. What am I doing wrong?

<?php
// Include WordPress bootstrap
define('WP_USE_THEMES', false);
require('path_to_wordpress_installation/wp-blog-header.php');

// Function to randomly update last_activity for 150 BuddyPress members with a specific role
function update_random_members_last_activity($role) {
    $users = get_users(array(
        'role' => $role,
        'number' => 150, // Limit the number of users to 150
        'orderby' => 'rand', // Order randomly
    ));

    foreach ($users as $user) {
        bp_update_user_last_activity($user->ID);
        // Optionally, perform other tasks with each user here
        echo "Updated last activity for user: " . $user->display_name . "<br>";
    }
}

// Call the function with the desired role
$role = 'your_role'; // Replace 'your_role' with the actual role
update_random_members_last_activity($role);

?>

I was expecting 150 members' last activity status to be randomly updated based on their role.