Hello. I am Gregory Lopez.
user
Hello, how may I help you?
assistant
I want to travel from DCA to DEN. Can you help me in booking a flight ticket?
user
Sure, may I know your trip dates?
assistant
I want to travel in the flight on Apr 20 and Apr 22.
user
Please wait for a while.
assistant
Ok, take your time.
user
Sorry, there is no flight available as per your request.
assistant
That's ok. Anyways, thank you for your help.
user
Most welcome.
assistant