You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Betty Taylor here. Can you please help me in changing my existing reservation, as I have to change it because my exams got postponed?

ASSISTANT: Sure, please wait a moment.

USER: Ok, sure.

ASSISTANT: Sorry, there is no active reservation on your name.

USER: Ok, not a problem. Anyways, thank you.

ASSISTANT: Thank you.