Did your organization recently move to "New" Microsoft Teams?
Some user preferences and settings may be activated by default or reset to default preferences.
For questions, consult your IT administrators for your internal policies and settings for Microsoft teams.
See support.microsoft.com article for more
New:
Microsoft Teams Activity notification preferences for new events in Outlook:
Enabled via Microsoft Teams settings as a user preference (See below how to modify this setting)
New events in Outlook:
Note: These do not show in outlook inbox when the M365 Admin: Mail Flow rules are enabled
Want to modify the Microsoft Teams activity preferences?
Go to Microsoft Teams > Settings >Notifications and activity
Calendar > New invites, updates and cancellations sent to me >
Show in activity and banner, Show in activity or Off
Change preference:
