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Near the bottom of the issue is the Activity section. This houses all communications and ticket history for the one ticket. The default view will show the "Comments" tab, showing all public and internal comments. Internal Comments are shaded yellow and will display "Internal note" at the top of the comment.
Reply to the Customer
To communicate with the Reporter and anyone in the Request Participant field, click on the "Reply to Customer" link. This will open a comment box and allow you to write and format the message.
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