You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Due to some health issue, I need to change my existing reservation. Can you assist me with that?

ASSISTANT: May I know your name?

USER: I am Anna Robinson.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name to change.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.