You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Can you please book the ticket from HOU to DCA? As I'm planning to visit Washington.

ASSISTANT: Sure, may I know your travel dates?

USER: Sure, my planned departure and return travel dates are 16th and 18th of Oct.

ASSISTANT: Please share me your name.

USER: My name is Brandon Brown.

ASSISTANT: Sorry, there is no flight at this moment.

USER: Oh! That's ok, thank you for giving the information anyways.

ASSISTANT: Thank you.