When Starting a new entry in 1PW, wrong autofill data appears

Hi  mcm30114​! Thanks for writing in. 

The list of suggested usernames comes from other login items in the selected account or vault. If username prefilling is on, your default identity or most commonly used username will appear automatically in the field. 

You can change the prefilled username by updating the personal details in your profile:

1. Open and unlock 1Password for Mac.
2. Edit an existing Identity item, or create a new one, add your preferred email to the email field, then save the item
3. Select Profile in the sidebar.
4. Click Select, or Update identity and choose the Identity item with the preferred email. 

You can also turn off the prefilling of usernames in 1Password for Mac: 

1. Open and unlock 1Password for Mac.
2. Click on 1Password next to the  in the menu bar.
3. Click Settings.
4. Turn off "Prefill username when creating a new login". 

If you're not actively using the items with your outdated email, you could also consider archiving them. If all the items using this email are archived, the email will no longer be suggested. Let us know if you have any questions, and thanks again!