You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Sarah Young.

ASSISTANT: How may I help you?

USER: I need a direct flight from DCA to IAD, please help me in booking a ticket.

ASSISTANT: Sure, may I know your journey dates please?

USER: My journey dates are 12/12 and 12/14.

ASSISTANT: Please wait a moment.

USER: Sure, take your time.

ASSISTANT: Sarah, no flights has been found on your journey dates.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for choosing us.