You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Edward Gonzalez. I planned world trip, so I want to start my journey from Philadelphia-PHL to Seattle-SEA.

ASSISTANT: If you have any planned travelling dates, could you please tell us?

USER: I am departing on 06/18 and return on 06/20.

ASSISTANT: Ok, please allow me a moment.

USER: Ok.

ASSISTANT: Edward, all flight tickets are sold out in your planned month.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you.