You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: I have planned to book a plane ticket to attend my office meeting in HOU, can you book a ticket from DFW?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: My preferred dates are June 20th and June 22nd.

ASSISTANT: Ok, could I have your name please?

USER: Katherine Campbell.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need single connection between my trip.

ASSISTANT: Ok, do you have any other specifications?

USER: No other requirements required.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: No problem, thank you for searching.

ASSISTANT: You are welcome, have a great day.