Around the end of August 2024, Google Calendar changed how holiday calendars work, and some dates that are not public holidays (such as observances) may be displayed as if they were holidays.
You can fix this by changing a setting in Google Calendar. Please follow the steps below.
How to change the setting
- Open Google Calendar settings in a web browser, then click "Add calendar" > "Browse calendars of interest".
- Under "Regional holidays", click the dropdown next to your country's holiday calendar and select only "Public holidays" (deselect "Other observances").