You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I have a business meeting in Phoenix. Can you help me for booking a flight ticket from IAH to PHX?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: My travelling dates are June 28 and June 30.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: Would you like to travel in a direct flight or a connecting flight?

USER: I need direct flight in my journey.

ASSISTANT: Do you have any other specifications?

USER: My return time is afternoon.

ASSISTANT: May I know your good name please?

USER: My name is Patrick collins.

ASSISTANT: Sorry, there is no flight available for your request.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for approaching us.