I Enter my business email address in the window that comes up next, and remove the checkmark from the “treat as alias” box. Then I click “next step”. But, the system return the specific error:
“Functionality not enabled.
You must send through resulteventos.com SMTP servers when you send as firstname.lastname@example.org. However, this functionality is not available for your account. Please contact your domain administrator for more information.”
You know why this happening?