Hello Thomas.

I inspected the page, and saw this error:

{"message":"Unable to add data in AmeliaBooking\\Infrastructure\\Repository\\Booking\\Appointment\\CustomerBookingRepository"}

This usually happens when you migrate the site, and the plugin's foreign keys aren't properly assigned, or when there are some missing Amelia tables in the database.

Either way, I'd need to remote in and take a look.

Please provide me a temporary WP-admin login for your site where this happens, so we could log in and take a look ‘from the inside’ as that’s the most efficient way to see and resolve the issue. We do not interfere with any data or anything else except for the plugin (in case that’s a production version of the site), and of course we do not provide login data to third party. You can write credentials here just check Private Reply so nobody can see them except us.

Please make sure to provide me with database access as well (PHPMyAdmin or C-Panel), so I can take a look at the database, and see what's going on.