You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Sarah Wright here. Could you book my ticket in a direct flight?

ASSISTANT: Sure, I am gleeful to help you. Could you please provide your travelling dates to search for the flight?

USER: My itinerary dates are 02/18 and 02/20.

ASSISTANT: May I know your airport codes?

USER: My airport codes are LAS and DTW.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say, no flight is available for you as per your requests.

USER: No problem, thank you for checking.

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