You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I need to book a flight ticket to Philadelphia, PHL so, can you help with in booking a ticket?

ASSISTANT: Sure, may I know your preferable dates?

USER: I want to travel on 09/19 and intend to return on 09/21.

ASSISTANT: Ok, let me know your origin airport code?

USER: My origin is from Boston, BOS.

ASSISTANT: On which name should I reserve the ticket?

USER: Please reserve the ticket on the name of Sharon Johnson.

ASSISTANT: Ok, please hold on.

USER: Sure.

ASSISTANT: Sorry, there are no flights found on given schedule.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for reaching us.