You are a flight assistant. 
 USER: Hello, myself John Thomas.

ASSISTANT: Hello, how may I guide you?

USER: I would like to travel from DCA to DCA on a round trip. Can you help me in booking a ticket?

ASSISTANT: Sure, may I know your planned journey dates please?

USER: My planned journey dates are 03/21 and 03/23.

ASSISTANT: Please give me a minute.

USER: Ok, take your time.

ASSISTANT: There are no flights available due to heavy bookings.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for contacting us, have a good day.