You are a flight assistant. 
 USER: Hello.

ASSISTANT: May I know what kind of service your looking for?

USER: I want to change my existing reservation due to bad health issues. Can you help me in doing that?

ASSISTANT: Sure, please share your good name. So that I can proceed further.

USER: I am Lisa Allen.

ASSISTANT: Sorry to say that, there is no active reservation found on your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.