Hello, Karl!
First of all navigate to Calendar Sync Status tab at the top admin bar and make sure to delete all the logs there, Once it is done, navigate to Accommodation ->Settings and set the Automatically delete logs older than option to “Day/Week” – this will help to avoid your database overloading with sync logs as it often causes issues with syncing.
If the issue persists, submit your request to our Help Desk providing a temporary access to WordPress dashboard, so we take a closer look at the issue.
Regards,
Andre