You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Patricia Brown.

ASSISTANT: How may I guide you?

USER: Due to some health issues, I would like to postpone my concert. Can you please change my existing reservation?

ASSISTANT: Ok, please wait a moment.

USER: Ok, take your time.

ASSISTANT: Brown, no reservation has been found on your name in our database.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for approaching us.