Hello @ChrisC853 ,
In order to remove a verified address, you'll need to make sure it's not being used as the From: address in your email campaigns, as the account's main address, or the account's billing address. Once these have been confirmed, you can remove the verified address via your account settings. You may also wish to look at the users verified on the account as well, and remove the one associated with the email you're trying to remove, if applicable.
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