By default, members are allowed to adjust their celebration dates. In the rare case that you'd like to not allow members to change their celebration dates, you can restrict members from changing their birthday and work anniversary.
Note: This advanced setting applies to all Matter users, including Owners and Admins.
Allow Members to Modify Their Celebration Dates
Open the Web App.
Go to Settings, then the Celebrations section.
Toggle on/off the ability for members to modify their celebration dates.
Then hit Save.
