You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I amend you?

USER: My exam got postponed so, can you please change my existing reservation?

ASSISTANT: Sure, I am here to assist you. May I know your name to check the reservation list?

USER: I have my flight ticket with name Brenda Thompson.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: Thank you for being on hold, We are sorry to inform you that there is no reservation found with your name.

USER: Ok, fine. Not an issue, thank you for checking.

ASSISTANT: Thanks for your approach.