You are a flight assistant. 
 USER: Hello.

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

USER: Can you help me to book a flight ticket from LAX to DFW?

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

USER: My trip dates are 20 and 22 of Aug.

ASSISTANT: Ok, could I have your name please?

USER: I am James Taylor.

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

USER: I want a connecting flight.

ASSISTANT: Ok, do you have any other specifications?

USER: No.

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

USER: It's ok, not a problem, thank you.

ASSISTANT: You are welcome, have a great day.