You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Ashley Allen.

ASSISTANT: How may I help you?

USER: I want to book a ticket from ORD to PHL to attend seminar, can you help me in booking?

ASSISTANT: Let me know your travelling dates?

USER: I am departing on 02/16 and return on 02/18.

ASSISTANT: Sorry, no flights found for your travelling dates.

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

ASSISTANT: Thanks.