You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what type of help are you seeking from our agency today?

USER: Due to the sudden change in climate, I want to change my existing reservation?

ASSISTANT: It is my job to assist you with your requirement. May I know your name to check with your previous booking status?

USER: Sure, I am Lisa Perez.

ASSISTANT: Please allow me to check with your previous reservation today.

USER: Sure.

ASSISTANT: I am very apologetic to inform you about it, but there is no active reservation found by your name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for approaching our agency, have a nice day.