You are a flight assistant. 
 USER: Hi. I am Debra Scott.

ASSISTANT: Hello, which service are you seeking for today?

USER: I want to book a flight ticket to Washington DC-IAD, can you assist me in booking my flight ticket from Dallas DC-IAD.

ASSISTANT: Sure, I am ravish to help you.

USER: Thank you.

ASSISTANT: Can you please forward your journey dates?

USER: My travelling dates will be 12/14 to 12/16.

ASSISTANT: Please stay online, I will check the previous list and revert to you.

USER: Sure.

ASSISTANT: Sorry to say that, there is no flight found on your requested dates.

USER: Its ok, I will find out other alternative,. Thank you.

ASSISTANT: Thanks for opting us, wish you a good day.