Month view wont work after update!

Hello everybody,

yesterday I updated my all of my plugins and my wordpress to the
latest versions.
After the update process I recognized something’s not working with
the calendar. But the error is only in the month view. So i changed
it to list and everything works fine, no error here.
But if i change it back to month view it wont stop loading the page
and it looks like it ends up with a loop.
After a couple of minutes it stops loading but still without any content
of my content section. So i also tried to downgrade the calendar version
to a older one but the error still exists. I already tried the plugin with the
default wordpress theme and the error is still there.
I dont know what it could be, i checked my code for any missing tags or open
tags but there is no mistake..

I really hope you guys can help me, because my costumer needs the month view..
btw, here is the site: Click here

Greeting from bavaria ??

https://www.ads-software.com/plugins/the-events-calendar/