You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me in booking a flight ticket from Phoenix, PHX to Houston, HOU?

ASSISTANT: Sure, please share your journey dates?

USER: My journey dates are from Sept 11 to Sept 13.

ASSISTANT: Do you have any specifications?

USER: I need a direct flight.

ASSISTANT: May I know your good name?

USER: My name is Thomas Allen.

ASSISTANT: Sorry, no flights found on your given details.

USER: Ok, that's not a problem. Thank you.

ASSISTANT: Thank you for choosing us.