You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Rebecca Williams.

ASSISTANT: Rebecca, how can I assist you?

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

ASSISTANT: Sure, let me check your reservation status first.

USER: Sure, take your time.

ASSISTANT: Rebecca, I have not found any reservation under your name in our database.

USER: Its ok, no issues. Thank you for the information.

ASSISTANT: You are most welcome and thank you for choosing us.