You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am Jacob Roberts.

ASSISTANT: Ok.

USER: Could you help me in booking a flight ticket from DC - DCA to PA - PHL?

ASSISTANT: Sure, I am here to help you. May I know your travelling dates?

USER: My departure day is 07/19, return day is 07/21.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no flights found on your requested travelling dates.

USER: No problem, thank you.

ASSISTANT: Thank you for approaching us, have a nice day.