First of all thank you for the great plugin. Unfortunately I get an error displayed when I booked a ticket.
Warning: Creating default object from empty value in / homepages/33/d462592410/htdocs/cms/wp-includes/capabilities.php on line 655
Delete my reservations, and the error is gone. The error is displayed in both the backend and the frontend.
I have already disabled all other plugins and switch to the default theme. The fault remains. Why is that?