You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: I want to book a direct flight to visit my friend's family. Can you book a flight for me?

ASSISTANT: Sure, let me know your planned journey dates?

USER: I will travel on May 31 and return on June 2nd.

ASSISTANT: May I know your airport codes please?

USER: My source airport is PHL and my destination is HOU.

ASSISTANT: Do you have any connection limit?

USER: I prefer a direct flight.

ASSISTANT: Can I know your name?

USER: My name is James Allen.

ASSISTANT: Is there any other specifications?

USER: No.

ASSISTANT: Thanks for your details, there is no flight found on your desired journey routes.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for opting us.