If you want to disable or enable celebrations for birthdays or work anniversaries in Matter, follow these simple steps:
How to Disable and Re-enable Birthday and Work Anniversary Celebration Messages
Open the Web App.
Go to Settings, then the Celebrations section.
Scroll down to either birthdays or work anniversaries:
In the Celebrations settings, you will see toggles for both birthdays and work anniversaries.
To disable either one or both, simply toggle the switch off (grey color). This will stop the automatic celebration messages for the selected option(s).
Click Save to apply your changes.