Customer context: The customer is a user of LiveAgent who is enquiring why the subject of a ticket did not change even though the client has updated it.
Customer: Why didn't the ticket subject change when the client updated it?
Answer: In your LiveAgent account, the setting "Update ticket subject from every received reply" is not activated in Configuration > Email > Email settings. Therefore, the subject does not automatically change when the customer updates it. Refer this link for more information: Automatic ticket subject update