No information from the pre-announcement is visible after I have added the booking number manually, I see a gray dot – Why is this?

The pre-notification has not yet been made in the ‘Notification Export Documentation’ service. The pre-notification might be made later. The equipment is currently not admitted to the terminal if it requires pre-notification. See here the overview of terminals that require pre-notification via Portbase. If you expected that the pre-notification has been made already, please contact the party responsible.