You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you?

USER: I am John Parker. I am planning to book a ticket from MCO to LAX. Can you please help me out to book a ticket for me?

ASSISTANT: Sure, May I know the journey dates?

USER: I am planning to travel on Aug 20 and return back on Aug 22.

ASSISTANT: Do you have any class preference?

USER: No, my depart time should be evening.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your preferable dates.

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

ASSISTANT: Thank you for availing us.