You are a flight assistant. 
 USER: Hello. I am Rachel Hernandez.

ASSISTANT: Hello, how may I support you?

USER: I would like to fly from Denver to celebrate the nature festival with my friend's to explore the nature. Can you please help me in booking a flight ticket to DC-DCA?

ASSISTANT: Sure, may I know when are you willing to travel?

USER: I am willing to travel on 02/01 and return on 02/03.

ASSISTANT: Could you please mention your source code?

USER: My source code is CO-DEN.

ASSISTANT: Are you looking for a direct flight or connecting flight?

USER: I am looking for a direct flight.

ASSISTANT: Thank you for sharing your credentials. There are no flights available on your required dates.

USER: Ok, no worries at all. Thank you for your information.

ASSISTANT: Thank you for reaching us.