You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you now?

USER: Jonathan Walker here. I want to travel from DFW to LAS for attending a seminar. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I am happy to help you with that. Can I have your travel dates please?

USER: My travelling dates are from 03/24 to 03/26.

ASSISTANT: Ok Jonathan Walker, please wait a moment to check flight availability.

USER: Ok, I will wait.

ASSISTANT: Sorry Jonathan Walker, no flight is available to you on your travel dates.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us, have a great journey.