You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may  I assist you?

USER: I have to attend my brother's marriage in Chicago, can you please help me to book my flight ticket from DFW to ORD?

ASSISTANT: Sure, I will help you out. Please provide me your travel dates?

USER: I want to depart on 12/13 and return back from ORD on 12/15.

ASSISTANT: Please wait a moment. May I know your name?

USER: Sure. My name is Anthony Hill.

ASSISTANT: Sorry Hill, no flights are available in your route.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for reaching us.