You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I am Katherine Campbell. I have to participate in the horse riding in Denver. Could you please help me in booking a flight ticket?

ASSISTANT: Sure, kindly mention your airport codes?

USER: My source code is Washington DC-IAD and destination code is Denver CO-DEN.

ASSISTANT: Can you please help me with your travel dates?

USER: My departure and arrival dates are 12/07 and 12/09.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to say, no flight found with your requirement.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: Thanks for reaching us.