You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you today?

USER: I am Catherine Jones. I want to book a flight ticket on 12/12 and return on 12/14, so can you help me with it?

ASSISTANT: Sure, could you please provide me your airport codes?

USER: Yes, my airport codes are CO-DEN and NV-LAS.

ASSISTANT: Ok, do you have any other requirements?

USER: I need a connecting flight.

ASSISTANT: Sorry to say that, no flights were available at your requested dates.

USER: That's ok.

ASSISTANT: Thank you for choosing us.

USER: Thank you for the response.