You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Barbara Hall.

ASSISTANT: How may I help you?

USER: My travel dates have been postponed, can you change my reservation?

ASSISTANT: Sure. Sorry, no reservation has been found on your name.

USER: It's fine. Thank you for your help.

ASSISTANT: Thank you for approaching us.Have a great day.

USER: Welcome.