How to Change Account to Married Name
To change the user name and email address of the user, please refer to the following steps:
1. Sign in to Office 365 Admin Center https://portal.microsoftonline.com with an admin account.
2. Navigate to users and groups.
3. Click the user and click the edit icon.
4. Click details.
5. Here you can change the name, display name and email address of the user.
Note: You might get a warning that the setting will take up to 24 hours to take effect.