You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you now?

USER: I want to change my existing reservation, due to some health issue. Can you please help me out?

ASSISTANT: Sure, I will help you with that? May I know your good name?

USER: My name is Jennifer Turner.

ASSISTANT: Please wait for a moment.

USER: Ok, I will wait for your information.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for visiting us.