How does Primary point of contact of a Service Request know that it is being converted into a Case

Summary:

User raises a Service Request and Agent converts it to a Case. How do the User know about this? And how does the conversation happen between the Case Manager and the Primary point of contact which in this case is the person who raised the service request

Content (please ensure you mask any confidential information):

User raises a Service Request and Agent converts it to a Case. How do the User know about this? And how does the conversation happen between the Case Manager and the Primary point of contact which in this case is the person who raised the service request