You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you now?

USER: I want to change my existing reservation, as my exams got postponed. Can you please help me with it?

ASSISTANT: May I know your name to check your booking?

USER: Myself Stephanie Carter here.

ASSISTANT: I found your booking, may I know your new travelling dates?

USER: That's great and thank you. My travel dates are Feb 27th and 29th.

ASSISTANT: May I know your airport codes too?

USER: My airport codes are LAS and AUS.

ASSISTANT: Do you need a connecting flight?

USER: No, I don't have any more specifications.

ASSISTANT: Sorry to say, there are no flights available for your journey.

USER: Ok, not a problem. Anyways, thank you.

ASSISTANT: Thank you for choosing us.