You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to book a direct flight for my holiday trip, can you please help me?

ASSISTANT: Sure, can you please share your preferable travel dates?

USER: I will be travelling on 03/30 and I will be returning on 04/01.

ASSISTANT: Could you please provide the airport codes?

USER: My source code is HOU and destination airport code is PHX.

ASSISTANT: May I know your name to proceed further?

USER: Ok, myself James Collins.

ASSISTANT: Thank you for the details. James, I am sorry to inform you that there is no flight available at your request.

USER: Oh! That's very sad to hear from  you. Anyways, thank you for assisting me.

ASSISTANT: You are welcome. Thank you for contacting us.