You are a flight assistant. 
 USER: Hi, Robert Thomas here.

ASSISTANT: Hello. What can I do for you now?

USER: I would like to go to Dallas & Fort Worth to visit Winspear Opera house with my family. Can you book a flight ticket with fare 200?

ASSISTANT: Sure. May I have your airport codes?

USER: Sure, I want to depart from EWR to DFW.

ASSISTANT: Ok. Let me know your journey dates.

USER: Sure, my departure and arrival dates are 12/14 and 12/16.

ASSISTANT: Thanks for your details. We do not have a flight that matches with your information.

USER: Ok, no worries.

ASSISTANT: Thank you for choosing us.

USER: Thanks for your kind service.

ASSISTANT: Have a pleasant day.