You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Carolyn Martinez.

ASSISTANT: How may I aid you?

USER: Please book a flight ticket from DFW to IAD.

ASSISTANT: Sure, may I know your journey dates?

USER: My trip dates will be 01/25 and 01/27.

ASSISTANT: Do you require any stopovers in your journey?

USER: I need a stopover and make sure that my departure time must be in afternoon.

ASSISTANT: Sorry, there are no flights found on your trip dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.