You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I be at your service today?

USER: Can you please help me to book a flight from HOU to OAK?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: Sure, I want to travel on Apr 7 and need to return on Apr 9.

ASSISTANT: Do you have any other specifications?

USER: I need a direct flight.

ASSISTANT: Please help me with your name for booking.

USER: Pamela Green here.

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

USER: Ok, not an issue. Thank you for the information.

ASSISTANT: Thank you for choosing us.