You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: I am planning to book a flight ticket to DCA from PHL, can you please help me out?

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: Sure, my planned travelling dates are July 16 and July 18.

ASSISTANT: Are you looking for a connecting flight or direct flight?

USER: I am looking for a flight with 1 connection.

ASSISTANT: Do you have any class preferences?

USER: I prefer economy class.

ASSISTANT: Do you have any other requirements that you are looking for?

USER: Yes, my airline must be within the normal cost.

ASSISTANT: Can you please provide your name to proceed further?

USER: Sure, my name is Donald Green.

ASSISTANT: Sorry, there are no flights available at your request.

USER: It's ok, thank you for the information.

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