Calendar App on all open Desktops

On my 24" iMac M1, OS 13.0.1

Recently my Calendar app appears on EVERY open desktop. I've closed it, rebooted the computer and reopened the app. Instantly shows on all open desktops. I can close the app on any desktop and they all go away. Reopen the app and it opens on all desktops. Doesn't make any difference if it's full screen or sized down. If I open new desktops and swipe right, there's a calendar on every one.

I like the app, always have. I've had this iMac for over a year, it did not do this immediately. But I'm not certain exactly when it started. I've looked at system settings and calendar settings and don't see any way to turn this on or off.

Appreciate any ideas or suggestions.

Jim Mays