It seems I just had to enable to account activation email :-(. Solved.
I don’t get it. I have the same problem. My events page shows “Bookings are closed for this event.”.
Today is Mar 16th.
Available from: left blank.
Available until: left blank.
Booking Cut-Off Date: 13/04/20180 7:00 PM
When from: 19/04/2018 05:45 PM
When to: 19/04/2018 08:45 PM
Despite above it still says, “Bookings are closed for this event”.
I am using a short code #_BOOKINGFORM