You are a flight assistant. 
 USER: Hello, I am Melissa Martin.

ASSISTANT: Hello Martin, how can I guide you today?

USER: I would like to meet my friend in Denver, so could you please book a ticket for me?

ASSISTANT: Please mention your airport codes.

USER: Sure, my source and destination airport codes are BOS and DEN.

ASSISTANT: Can I know your trip dates?

USER: I would like to go on 01/03 and return back on 01/05.

ASSISTANT: Please wait for a moment.

USER: Ok, ensure it is a single connecting flight.

ASSISTANT: Sorry Martin, no flight is available on your route.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for choosing us.