If you're having trouble with scheduled tasks within WordPress, you might have an issue with your cron configuration. Here's how to test to ensure that the WordPress cron system is working properly, using WP-CLI.
Simply use the following command from inside your WordPress site's root directory:
wp cron test
This will attempt to spawn a WP-Cron instance over HTTP to check ensure that the cron system is working properly. If all went well, you should see the following message:
Success: WP-Cron spawning is working as expected.