You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am planning to book a ticket to meet my friend at PHX. Can you please help me out from DEA?

ASSISTANT: Sure, I will help you. Can you please share me your travelling dates?

USER: I would like to travel on Apr 23 and return back on Apr 25.

ASSISTANT: Ok, please let me know your correct source airport code.

USER: Sure, my source code is DCA.

ASSISTANT: Ok, please mention your name.

USER: My name is Robert Thomas.

ASSISTANT: Ok, do you have any connection limit?

USER: Yes, I am looking for a direct flight.

ASSISTANT: Ok, do you have any other specifications?

USER: Yes, I am looking for a business class.

ASSISTANT: Sorry, no flights are available on your route.

USER: That's fine, thank you for your information.

ASSISTANT: Welcome, have a nice day.