You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am Brian Nelson. Can you please find a flight and book a flight ticket to CO-DEN from TX-IAH. Could you please help me with booking a flight ticket?

ASSISTANT: Sure, I am here to help you, may I know your travelling dates?

USER: My travelling dates are 03/15 and 03/17.

ASSISTANT: Could you state your price limit?

USER: I can pay up to 200.

ASSISTANT: Sorry Brian Nelson, no flights found on your requested dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for approaching us.