You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I want to book a ticket from LAS to IAH.

ASSISTANT: Sure, please provide your travelling dates.

USER: Departure date is May, 18 and return is by May, 20.

ASSISTANT: Do you have any requirements?

USER: I need a connecting flight.

ASSISTANT: Sorry to inform, there is no connecting flight available with your criteria.

USER: Thanks.

ASSISTANT: May I know your name please?

USER: My name is Dennis Thompson.

ASSISTANT: Thank you for choosing us.