It seems that the scheduler and web logic hooks are simply queuing up and not getting executed.
Kindly suggest how to fix this issue.
Before digging into any jobs that are stuck, can you confirm the cronjob is running on the server?
You could also run the cron.php manually to see if that triggers the schedulers.
If the cronjob is running and executing the cron manually does not process any schedulers you can run the following on the database:
SELECT * FROM job_queue WHERE status = 'running';
If there is a scheduler running for a long time then it would need to be investigated why that is and if that process can be canceled.
Let me know if it was one of those.
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