You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Larry Rodriguez.

ASSISTANT: How can I serve you?

USER: As I planned for a holiday trip with my friend's to Dallas & Fort Worth. Can you please book a flight ticket?

ASSISTANT: Sure,May I know your travelling dates?

USER: My departure and arrival dates are 02/12 and 02/14.

ASSISTANT: Share me your preferable airport codes.

USER: I would like to deviate from Denver CO-DEN to Dallas & Fort Worth TX-DFW.

ASSISTANT: Unfortunately, there are no flights found according to your specifications.

USER: Ok, no worries at all. Thank you for your information.

ASSISTANT: Thank you.