You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, may I know your good name please?

USER: I am George Harris.

ASSISTANT: May I know what kind of service you are expecting from us?

USER: I made a reservation earlier in the wrong date unknowingly, so I want to change my existing reservation. Can you help me in changing my existing reservation?

ASSISTANT: Sure, I am at your service. Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, but there is no reservation found on your name.

USER: It's ok, not an issue. Thanks for your kind response.

ASSISTANT: Thank you for opting us, have a great day.