Scheduled posting not working, publicise stopped working also

Hello,

My problem on the website seems to be two fold, firstly Publicise through Jetpack stopped working on scheduled posts. The post would be published at the scheduled time.

Overnight the problem has escalated insofar as now posts are not being published through scheduler.

I have removed a couple of themes and plugins that are more recent to no avail. The sight seems to have slowed down also.

Would you have any insight to what might be going on?

Thanks in advance for your help.