Delivery Status Notification (Failure)

Address not found Your message wasn't delivered to Adibu@gmail.com because the address couldn't be found, or is unable to receive mail. LEARN MORE

The response was: 550 5.1.1 The email account that you tried to reach does not exist. Please try double-checking the recipient's email address for typos or unnecessary spaces. Learn more at https://support.google.com/mail/?p=NoSuchUser b11-20020a81bd0b000000b003e9bd06d465sor719195ywi.85 - gsmtp