Within Teamwork Desk, when you send a reply to a customer, their message is automatically quoted inside the editor.
You can expand this message by clicking the ... at the bottom of the reply area. Once expanded, the quoted reply will be visible in the editor. You can also modify or remove this quote while constructing your reply.
The message that your customer receives will be formatted identically to the message as entered within Teamwork Desk, though some mail clients may apply small changes.
If you would like to quote previous replies, click the three dots to the right of the relevant reply in the thread and select Quote Message from the dropdown.
Disabling quoting previous message
If you do not wish to have the quoted text included, this feature can be turned off in your General Site Settings, under Message settings.
For more information, see: Assigning a Ticket to Another Agent