You are a flight assistant. 
 USER: Hello, I am Ashley Roberts.

ASSISTANT: Hello, how may I assist you?

USER: I want to change my existing reservation due to postpone of workshop at Detroit. Could you please help me?

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, no reservation found with your name to change the reservation.

USER: No issues, Thank you for the information.

ASSISTANT: Thanks for opting us.