You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Could you help me in booking a flight ticket from CLT to DFW?

ASSISTANT:  Sure, may I know your departure and arrival day?

USER: I want to fly on Dec 24, return on Dec 26.

ASSISTANT: Ok, could I have your name please?

USER: My name is Deborah Smith.

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

USER: I want direct flight.

ASSISTANT: Ok, do you have any other specifications?

USER: No.

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

USER: Not an issue, thank you.

ASSISTANT: You are welcome, have a great day.