You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am planning to visit Atlanta with my friends. Can you do the reservation?

ASSISTANT: Sure, may I know your source and destination airport codes?

USER: My airport codes are IAD-ATL.

ASSISTANT: Do you need halt in between your journey?

USER: I need halt in my journey.

ASSISTANT: May I know your depart and return dates?

USER: My travelling dates are 03/19 and 03/21.

ASSISTANT: May I know your name please?

USER: Donna Jones here.

ASSISTANT: Sorry, there are no flights found with your given dates.

USER:  No problem, Thanks for the information.

ASSISTANT: Thank you for choosing us.