You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I assist you?

USER: Can you help me to book a flight ticket from LAS to HOU?

ASSISTANT: Sure, May I know the journey dates?

USER: My travelling dates are 10 and 12 of Feb.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: Is there any other requirements?

USER: I would like to depart in the evening.

ASSISTANT: May I know your name?

USER: I am Kevin Brown.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

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

ASSISTANT: Thank you for opting us.