You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: Can you please help me in changing my existing reservation, as my exams got postponed?

ASSISTANT: May I know your name?

USER: Thank you for the response, my name is Joseph Hill.

ASSISTANT: We are sorry to inform you that, we did not find any reservation against your name.

USER: Ok, not an issue. Anyways, thank you for the help.

ASSISTANT: Thank you.