You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I best assist you now?

USER: I am Helen Allen, I want to change my reservation as my journey date is postponed. Can you help me with that?

ASSISTANT: Sure, may I know your good name please? Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry there is no reservation found on your name.

USER: Ok, thank you for the information.

ASSISTANT: Thanks for connecting us, have a great day.