You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am planning to book a ticket from LAS to IAH. Can you please help me out to book a ticket for me?

ASSISTANT: Sure, can you please share your travelling dates?

USER: I am planning to travel on Dec 02 and return back on Dec 04.

ASSISTANT: Do you want connecting flight or direct flight?

USER: I am looking for a connecting flight.

ASSISTANT: Is there any other specifications?

USER: No.

ASSISTANT: May I know your name?

USER: My name is Donna Thomas.

ASSISTANT: Sorry, there are no flights found based on your details.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you for choosing us.