Using the New Outlook for Mac for personal email and calendar
Hi,
I will walk through a few steps with you. Some of these are just to help figure out what is wrong, not to fix it right away. So if nothing changes after a step, that is normal. I will keep going until we solve it.
If it is an Outlook account, can you get rid of the addresses from OWA : https://outlook.live.com/
If the X is also not there, you can add the incorrect address to the address book and then delete it. After doing that, it no longer appears as per other users.
I hope this information helps. If you have any more questions, don't hesitate to reach out. Wishing you good luck!