Windows 10- Birthday notifications on lockscreen and no way to disable?

 https://answers.microsoft.com/en-us/windows/forum/all/windows-10-birthday-notifications-on-lockscreen/bf1aa6a5-49e2-4a97-a2c9-e72813533475?auth=1

We would like to verify, have you tried modifying the Lock screen settings? If not yet, here's how:

1. Go to Windows Settings by pressing Windows key + I.
2. Click Personalization.
3. Select Lock screen from the list on the left.
4. Under the section Choose an app to show detailed status, click the calendar icon.
5. Once you click the icon, select None.