Each and every Helpdesk ticket that is entered into CNAV is assigned a unique ticket ID. You can use this ticket ID later to search for a specific ticket.
Note that ticket IDs are not assigned sequentially within the CNAV Helpdesk system. In fact, you may submit two tickets only moments apart and have those tickets assigned ID numbers thousands of digits apart. This processing occurs because the Helpdesk ticket IDs are actually also CNAV entity IDs. Every "entity" within CNAV is assigned a unique ID regardless of whether that entity is a Helpdesk ticket, a group, a course, or a person. Because the fields used to store these IDs are sufficiently large, processing is not affected and, due to certain especially elegant internal algorithms, is actually made more efficient by this usage.