I have a user that has been constantly getting locked out, averaging 3 times a day for months. I have looked and looked and didnt find anything that was causing the lockouts.
So I decided to create a new active directory user, same rights and permissions and re-assign the O365 email account to that new (same person) AD account.
O365 admin portal wont let me re-assign the email address and mailbox to the new AD account. it still exists and I can resurrect it , cloud only but how do I get it back and assign like I want to ?