You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I serve you?

USER: I would like to book a flight from DCA to SFO to meet my parents.

ASSISTANT: Sure, We are here to assist you. Can I know your travelling dates?

USER: My travelling dates are Feb 27 and Feb 29.

ASSISTANT: Do you need any break?

USER: I  prefer to travel in a direct flight.

ASSISTANT: May I know your name?

USER: I am Robert Allen.

ASSISTANT: Is there any other specifications?

USER: No.

ASSISTANT:  We are unable to provide flight in between your journey routes due to some technical up-gradation at destination airport.

USER: No worries, thank you for the information.

ASSISTANT: Thank you for picking us.