You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I am planning to visit the Mount Evans which is located in Denver, DEN. Can you help me to book a flight ticket?

ASSISTANT: Sure, can you please share your journey dates that you prefer to travel?

USER: My travel dates are July 14 and 16.

ASSISTANT: May I know your source airport code?

USER: My source is from Austin, AUS.

ASSISTANT:  Do you require any stopovers in your journey?

USER: No, I need to travel in direct flight.

ASSISTANT: Is there any class preferences?

USER: No.

ASSISTANT:  Would you let us know if you have any other preferences?

USER: I don't have any other preferences.

ASSISTANT: May I know your name?

USER: Eric Anderson here.

ASSISTANT: Ok, please wait a minute I will get back to you with the flight details.

USER: Sure.

ASSISTANT: Sorry to say, no flights found with your requirement.

USER: Ok, thank you.

ASSISTANT: Thanks for reaching us.