You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: My self David Lewis, I need to schedule my trip to Chicago for next week. Could you please help me ion booking the ticket from BOS to ORD?

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

USER: I will take-off 07/11 and again I will be return back on 07/13.

ASSISTANT: Ok, please wait for a while.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for waiting. Sorry Lewis, there are no flights available.

USER: Not an issue, anyhow thank you very much for your help.