You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Can you please help me in changing my existing reservation, as I have a meeting on the same day?

ASSISTANT: Sure, may I know your name?

USER: My name is Jack Hernandez.

ASSISTANT: We found on your reservation, could you please help me with your airport codes?

USER: My airport codes are AUS and DCA.

ASSISTANT: Can you please help me to with your journey dates?

USER: My travelling dates are Sep 2nd and 4th.

ASSISTANT: May I know your other preferences?

USER: I need a single connecting flight.

ASSISTANT: Sorry, we could not find any flight on your request.

USER: Ok, no problem. Anyways, thank you.

ASSISTANT: Thank you for choosing us.