"The mail system at host soproxy12.mail.unifiedlayer."

I've received a few email ""bounce backs" from "host soproxy12.mail.unifiedlayer." I saw that email addressed buried deep inside a thread here, and I'm perplexed: the email is not being received, and the "only" hint of a scam is in bold below:

This is the mail system at host soproxy12.mail.unifiedlayer.com.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

The mail system

<redacted>: host gmail-smtp-in.l.google.com[142.250.141.26] said:
550-5.7.26 This message does not have authentication information or fails
to 550-5.7.26 pass authentication checks. To best protect our users from
spam, the 550-5.7.26 message has been blocked. Please visit 550-5.7.26
https:/ /support.google.com/mail/answer/81126#authentication for more 550
5.7.26 information. ob12-20020a17090b390c00b001bf576ca141si4143709pjb.1 -
gsmtp (in reply to end of DATA command)

It looks like you're getting a message from gmail saying an email you've sent has been blocked due to an authentication issue.

What you need to determine is if it's an email you sent that's bounced back, or if someone is trying to spoof your email address. it could be something as simple as you need to change your ip address.