Had a customer with this issue, and I personally have never had to do this. It turns out to be pretty easy.

• Start a new email
• Start typing the email address you want to remove.
• When the name shows up, highlight it, and delete it.

The following link lead me to the answer.

https://www.lifewire.com/delete-address-from-auto-list-outlook-1173778

Let us know if this helped you…