No errors at all. Just a blank page where the calendar usually appeared.
I’m having the same problem. The calendars were working fine for over a week. I have 13 on one website. Starting yesterday they no longer save bookings. I created a test calendar and it worked fine. Recreating all 13 calendars with bookings would be a huge PITA and I’m not certain it won’t happen again. Did the problem return with your new calendar?
This has been working fine up to yesterday and I’m not getting any errors. Also don’t have a firewall plugin. I’ve emailed support and await their response.