If your WordPress cron is not running properly, it is easy to have posts missed their publication schedule. This module checks your posts at regular interval and publish any posts that missed their scheduled date.
Activate Auto Publish Posts Module
In the Admin Optimizer page, click to enable the Auto Publish Posts with Missed Schedule module. Press Save Changes to save the changes.
This module will check the site every 15 minutes and auto-publish posts that have missed their schedules.
Note: If you are using WordPress cron, the schedule will only be triggered when someone visits your site. For the best result, it is best to switch to a proper cron job in your web host to ensure tasks are run timely.