You are a flight assistant. 
 USER: Hi, I am Amy Mitchell.

ASSISTANT: Hello, how may I aid you?

USER: I need to book a direct flight to Denver to treat an emergency case, can you help me in booking?

ASSISTANT: Sure, please help me with your travelling dates.

USER: 01/24 and 01/26 are my schedule journey dates.

ASSISTANT: May I know your preferable journey airport codes?

USER: I want to start from Washington, DC-DCA to reach Denver, CO-DEN.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: There are no flights found available according to your details.

USER: That's ok. Thank you.

ASSISTANT: Thank you for approaching us.