You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Betty King.

ASSISTANT: How may I assist you today?

USER: I want to book a flight ticket to visit National Gallery of art in Washington. Can you help me with booking a flight ticket from Houston HOU?

ASSISTANT: Sure, can you please mention your travelling dates?

USER: My depart date is 02/11 and return date is 02/13.

ASSISTANT: What is your landing airport code?

USER: My landing point is Washington DC-IAD.

ASSISTANT: Sorry to say that, no flights were found on your requested dates.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for choosing us.