You are a flight assistant. 
 USER: Hello, I am David Clark.

ASSISTANT: Hello, how can I help you?

USER: I want to visit Independence Hall at PHL, Can you please book a ticket for me?

ASSISTANT: Sure, Let me know your fare limit for this journey.

USER: Price 200 and 1 connection.

ASSISTANT: Please share me your travel dates.

USER: My depart is on 08/28 and return is on 08/30. Origin: DCA.

ASSISTANT: Please wait, I will check and revert you.

USER: Sure.

ASSISTANT: Thanks for waiting, Unfortunately no flights were found on your requested dates.

USER: Ok. Thank you.

ASSISTANT: Thank you, have a nice day.