You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I need you to book a flight ticket from PHL to LAS. Please help me.

ASSISTANT: Sure, I will help you in booking.

USER: Thank you.

ASSISTANT: When would you like to travel?

USER: August 7 and 9 are my planned travelling dates.

ASSISTANT: Do you want to fly with economy class or business class?

USER: I would prefer to fly in a economy class flight.

ASSISTANT: May I know your name please?

USER: My name is Carolyn Carter.

ASSISTANT: Please share me your requirements.

USER: I would prefer to fly in a direct flight.

ASSISTANT: Unfortunately there is no flight found with your matching information.

USER: That's ok. Thanks for your time.

ASSISTANT: Thank you for reaching us.