You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I  help you?

USER: I need to book a ticket from IAH to BOS. Could you book a ticket?

ASSISTANT: Your travelling dates please?

USER: Travelling dates are Aug, 5 and Aug, 7.

ASSISTANT: Do you have any specifications?

USER: I prefer connecting flight.

ASSISTANT: Any thing else?

USER: I would like to depart in the afternoon.

ASSISTANT: May I know your name please?

USER: My name is Catherine Collins.

ASSISTANT: I am sorry no flight found on your route.

USER: Thank you.

ASSISTANT: Thank you for choosing us.