Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello Andrea,
As you posted the thread on My account billing and sign in/Mac category, may I know if you are using Outlook for Mac or Outlook Web App to send emails?
Anyway, based on your description, my understanding is that you want to change the display name in your sent emails, it may look like Andrea xxx, not your full email address, please clarify if I misunderstand your text.
If you are using Office 365 account to send emails, as far as I know if you want to change the display name in the sent emails, first you need to contact your global admin to help you change the display name for your Office 365 mailbox, then it may take some time to take effect in the sending or receiving emails. For more details, please refer to https://docs.microsoft.com/en-us/office365/admin/add-users/change-a-user-name-and-email-address?view=o365-worldwide > Change a user's display name.
On another hand, if this is not your scenario, could you please share some generated screenshots and add some more clarifications about what you want to change and what account you are using, like Office 365 account, Outlook.com etc. I am willing to help you do more research, thanks.
Hope it is helpful for you.