You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: Can you please help me to book a flight ticket from JFK to IAH?

ASSISTANT: Sure, could you please share your trip dates?

USER: My travelling dates are Apr 16 to Apr 18.

ASSISTANT: Ok, could I have your name please?

USER: I am Pamela Hall.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need a connecting flight.

ASSISTANT: Ok, do you have any other specifications?

USER: I want to depart in the evening.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: No problem, thanks for your information.

ASSISTANT: You are welcome, have a great day.