You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I need your help to change my travel dates in my existing reservation so can you please help me with that?

ASSISTANT: May I know your name?

USER: Sure, my name is Sarah Baker.

ASSISTANT: Please wait.

USER: Ok.

ASSISTANT: Sorry, no reservation found on your name.

USER: That's ok, no problem. Thank you for your service.