You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I need to book a flight ticket from LGA to DFW, can you help me in booking a flight ticket?

ASSISTANT: Sure, may I know your trip dates please?

USER: Sure, my scheduled dates are Jul 13 and Jul 15.

ASSISTANT: Do you have any other requirements?

USER: I prefer a direct flight.

ASSISTANT: Can I know your name please?

USER: Sure,.

ASSISTANT: Ok, please wait for a while.

USER: Sure, Scott Thomas here.

ASSISTANT: Sorry, we regret to inform you that there is no flight available as per your request. Thank you for approaching us.