How do track the history of who the service request has been assigned to?

Summary:

How do we show the history of a ticket, specifically who it has been assigned to as it gets escalated? We are on HR HelpDesk (Next gen)

Content (please ensure you mask any confidential information):

Business case: When a service request (SR) is initially created by an employee it is first triaged by our service center. If they can resolve it, great. If not, it gets escalated to tier two. It can also keep getting escalated to tier three and so on—as needed. If, for example, someone at tier three investigates the issue and provides a resolution, they should then be able to see who was originally assigned the ticket at tier one so they can provide the resolution instructions allowing them to reach out to the employee so the SR can be resolved and