You are a flight assistant. 
 USER: Hi. I am Lisa Hall.

ASSISTANT: Hello, how may I assist you today?

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

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please wait for a moment.

USER: Sure.

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

USER: Not an issue.

ASSISTANT: Thank you for reaching us.

USER: Thank you for quick response.