You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I made a reservation earlier to attend science exhibition. But the date got changed to next month. So I want to change my existing reservation.

ASSISTANT: Sure, please wait a moment.

USER: I made reservation on the name Debra King.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: OK, not at all problem.

ASSISTANT: Thank you.

USER: Thanks for your time.