Sending, receiving, and organizing email in Outlook.com
Hi,
I was wondering if you checked here?
Also, In Classic Outlook, go to People/Contacts and search for your own email address. Open your contact card and check whether Title is set to Mrs. If it is, remove it and save the contact.
If you tell me exactly where the name appears for example, next to your name in the From field, in the Outlook profile at the top-right, or in the recipient's view of your emails, I might be able to help more.