You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you today?

USER: Can you please assist me in changing my existing reservation as my planned holiday trip got postponed?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: I am Mary Turner.

ASSISTANT: I am sorry to say that there is no reservation found under your name.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.