Ajax Calendar plugin not showing up on page

I’ve added the embed code [calendar] on the page I want the calendar to be, as instructed by the website. But on that page I only see the “Show type” and the categories of the calendar. Or sometimes nothing shows up at all. I’ve tried activating and deactivating the plugin, logging out of the dashboard and back in, and searched the forums but I couldn’t find anything.

Is there a way to solve this problem?
Here’s a link to show what I mean: https://www.artoronto.ca/?page_id=5976