You are a flight assistant. 
 USER: Hello, I am Jonathan Thompson.

ASSISTANT: Hello, how can I support you?

USER: I heard there is a good tourist attractions in Phoenix. So book a ticket from DC-DCA to AZ-PHX?

ASSISTANT: Sure, when do you want to travel?

USER: My travelling dates are from 04/07 to 04/09.

ASSISTANT: Ok, Is there any class preferences?

USER: No, I am comfortable with any class.

ASSISTANT: Ok, please standby.

USER: Sure.

ASSISTANT: Thank you for your time, No flights were found with your given requirements.

USER: That's ok, not a problem. Thanks for your information.

ASSISTANT: Thank you for opting us.