Managing personal Outlook.com account settings, security, and privacy
Hi,
An alias is also known as an email address.
- Sign in to your Microsoft account at https://account.live.com/names/manage.
- Under Account aliases, locate the alias you want to remove.
- Select Remove next to the alias.
- Confirm the removal.
Please note that If the alias is an Outlook.com, Hotmail.com, or Live.com email address, removing it permanently deletes the alias and it cannot be reused.
I look forward to hearing from you to get the results of the troubleshooting.