You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: I want to change my existing reservation due to sudden change in my meeting location. Can you please help me with this?

ASSISTANT: Sure, may I know your good name?

USER: Sure, my name is Donald Williams.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no recent reservation.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you.