Hey there @cmthorley, that does sound quite odd. You weren't cc'd into those emails you're receiving or anything like that?
If those emails aren't intended for you or just spam as you've mentioned, I recommend flagging the email as spam.
If you do have any other questions, we can assist further. We would just need you to send us a message via the My Optus App so we can verify your details. We're unable to discuss your account on Yes Crowd as it's a public platform.