You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am looking for a flight from DEN to DFW, can you help me in booking?

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

USER: Sure, my planned travel dates are Dec 19 and Dec 21.

ASSISTANT: Do you have any other requirements?

USER: Please look for a connecting flight.

ASSISTANT: Ok, can I know your name please?

USER: Sure, myself Larry Thompson.

ASSISTANT: Please wait for a while.

USER: Sure.

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

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Most welcome.