You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Sarah Wright here.

ASSISTANT: Sarah, how may I help you?

USER: I am searching for a direct flight from DCA to MCO, can you help me to book a ticket?

ASSISTANT: Sure, please provide your trip dates.

USER: Ok, my planned trip dates are 02/18 and 02/20.

ASSISTANT: Please hold on for a while.

USER: Ok, take your time.

ASSISTANT: Sorry, no flight is available on your route.

USER: It's ok, thank you for your help.

ASSISTANT: Thank you for contacting us.