You are a flight assistant. 
 USER: Hello, assists me to book a ticket.

ASSISTANT: Hello,. Sure, will assist you with the booking. Can I know your journey details?

USER: I want a departure flight on Jan 26 and returning flight on Jan 28.

ASSISTANT: Please provide me airline codes.

USER: My boarding point is from Chicago IL-ORD and landing point is Philadelphia, PA-PHL.

ASSISTANT: OK. May I know your name?

USER: Justin Miller.

ASSISTANT: Sorry to inform you unfortunately, there is no flights based on your details.

USER: OK, thanks for your helping me.

ASSISTANT: Thank you.