You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am planning to change an existing reservation, due to health issue. Can you please help me out?

ASSISTANT: Sure, may I know your name please?

USER: My name is Cynthia Moore.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: There is no reservation found with your given name.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you.