You can turn one ticket into two separate tickets. The new ticket will contain the responses you selected to split from the original ticket, while the original ticket will contain all the responses you did not select. During the splitting process, you can also link the new ticket to the original one.
In the Reply and Comment section, click Split in the ticket response you want to split off from the current ticket, or select several responses to split off and click Split selected. The Split Ticket page appears.
In the New ticket subject field, enter the subject of the split ticket.
In the Link Tickets field, select the relationship the new ticket should have to the original ticket.
In the Internal Ticket field, select Yes if this split ticket is viewable only to internal users. Select No if you want the client to be able to view the new ticket.