You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Robert Lee from Houston.

ASSISTANT: How can I help you?

USER: Could you please help me in flight ticket booking process from HOU to IAD?

ASSISTANT: Let me know your travel dates.

USER: Thank you for your response, I want to take off on Oct 03 and book my return ticket also on Oct 05.

ASSISTANT: Do you have any preference?

USER: I want to return in evening time.

ASSISTANT: Connecting flight can be booked with airline Spirit for price 100 having flight number 1003.

USER: Please confirm this flight ticket for me.

ASSISTANT: Ticket is booked.

USER: Thank you for your help.

ASSISTANT: Thank you.