You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Help me in booking a flight from DFW to LAS?

ASSISTANT: Sure, we are blissful to help you. May I know your travel dates?

USER: My travelling dates are Jan 01 to 03.

ASSISTANT: Do you need any way station in your journey?

USER: I prefer direct flight.

ASSISTANT: May I know your specific time to travel?

USER: I am comfortable in any time.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: We are regret to inform you that, there are no flights available with your specifications.

USER: That's ok, thank you.

ASSISTANT: For documentation, may I know your name please?

USER: I am William Evans.

ASSISTANT: Thank you for reaching our services, we will try to serve you for the next time.