How did our Sender email change to noreply@'company'com

Summary:

As of Monday 4/21/25 users stated they were receiving emails from Sender email "noreply@dexcom.com" instead of the ecxg email
"ecxg.fa.sender.2@workflow.mail.us2.cloud.oracle.com"

This is only happening in our Production instance. In our Dev instances the email address still shows as EX. Dev2 instance "ecxg-dev2.fa.sender.2@workflow.mail.us2.cloud.oracle.com"

We received the 25A patch in our Prod environment last Saturday 4/19/25

Can you point me to where I can locate where the update may have been? Also, is there an audit trail to show who might have changed the Sender email? Any other ideas?