You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you today?

USER: Owing to an emergency, my business conference got postponed. So I want you to change my existing reservation.

ASSISTANT: Sure, I'll help you in changing an existing reservation. Could you please let me know your name to check the reservation status?

USER: Sure, I have a recent reservation with name Anthony Lee.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry to inform you that there is no reservation found by this name.

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

ASSISTANT: Thank you for opting us.