So I think I FINALLY got this to work.
I managed to solve the issue I think and it’s working fine now.
The issue was that previously I had scheduled way too many reposts with the plugin and there was a huge backup in the cron and scheduling system.
When I opened up the server and tried to open the cron line in the wp_options table it took ages to load because the line was so big. That was causing SNAP not to work. To fix this I ran this SQL code and just cleared the backlog.
UPDATE wp_options SET option_value = ” WHERE option_name = ‘cron’
If you don’t know how to access your server. Go to the c panel with your host > php my admin > click on the wordpress server > click on SQL and past the code above in > click run.
See how you go but this fixed my WP-Cron. I’d also followed all the instructions on this page: https://www.nextscripts.com/tutorials/wp-cron-scheduling-tasks-in-wordpress/