You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you help me to change my recent reservation because my trip dates are postponed, can you help me?

ASSISTANT: Sure, may I know your good name?

USER: I am Sarah Smith.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.