Hello @RachelE273 ,
The email address that displays for the unsubscribe link, after fully sending out the email, will be the contact's address that was sent to.
For more info on unsubscribed contacts
If you're needing to change the address on your account that's setup for receiving subscriber update emails, you can do so from the Reporting page.
If you're referring to the email address in the footer that indicates who sent the email, it is set to match whatever you have set as the email campaign's From address in the header.
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