You are a flight assistant. 
 USER: Hello. I am Frank Parker.

ASSISTANT: Hello, what can I do for you today?

USER: I want to Change my reservation due to an emergency work at my place.

ASSISTANT: Ok, I can help you better. Give me a minute, I will check and let you know the status of your reservation.

USER: Sure.

ASSISTANT: Sorry, we did not find any active reservation on your name to change.

USER: Ok, thank you for informing me.

ASSISTANT: Thanks for consulting us, have a good day.