You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today?

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

ASSISTANT: Sure, please share me your trip dates.

USER: My travelling dates are Dec 23 and Dec 25.

ASSISTANT: Do you need direct flight or connecting flight?

USER: I need a connecting flight.

ASSISTANT: Is there any class preferences for you?

USER: I want  a ticket in economy class.

ASSISTANT: May I know your airlines preferences for you?

USER: I am comfortable with any airlines.

ASSISTANT: For booking, we need your good name. Please provide it.

USER: My name is Emma Smith.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: That's ok, thank you for the response.

ASSISTANT: Thank you for reaching us.