You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Debra Roberts here. Can you please help me to book a ticket from DFW to ORD?

ASSISTANT: Sure, could you please provide your willing dates to travel?

USER: I want to go on 09/27 and return on 09/29.

ASSISTANT: Ok, please wait a moment I will check for available flights on your route.

USER: Sure.

ASSISTANT: Sorry to say, no flights were available on your dates.

USER: No problem, thanks a lot.

ASSISTANT: Thank you for reaching us, have a nice day.