Just 1 Upcoming Event is not showing up in the Summary Block which shows all events??

Site URL: https://www.scriptanatomy.com/course-calendar

On our website, we add all of our courses to our Upcoming Courses page which is our not linked Events page: https://www.scriptanatomy.com/upcoming-courses

On our Course Calendar page, we have a summary block which lists all of our upcoming events: https://www.scriptanatomy.com/course-calendar

There is just one single courses that is not showing up on the course calendar page. It does show up on the Upcoming Courses page, it's the one titled, "*2021 NEWLY ADDED* Structure Lab (Drama Focus)" on January 9th. However, it doesn't show up on the Course Calendar page. This has never happened before and I can't figure out what the problem is.

I tried deleting and adding the event again, removing and adding the tags again, changed the url structure a bit just to see, and even changed the end time by one minute. I tried the last thing, changing the end time, because the only thing I could think of is that the date and time is exactly the same as another event. However, this shouldn't be a problem because there are other events with the exact same date and time that both show up.

Any ideas??