How to configure the default "Change by" and email sender on ticket notifications

[Ed Warkentin]

When a new ticket is generated (e.g. employee sends an email to our IT help desk email address), Jira Service Management reports the new ticket and default changes as generated by one specific IT admin in our group. 

Is there any way to suppress this or make the change more generic?

e.g. Here's the email notification, always from the same guy. 

Eugene D**** updated HD-3503

Change By: Eugene D****
Status: Waiting for support customer

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Looked high and low, but cannot find out where can we change that default user name?

[Ed Warkentin]

Update, I think the field is default.event.user  

Where can this be found in the config settings for the given project. (Jira Service Management)?