You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Can you please help me in flight ticket booking process from IAH to DCA?

ASSISTANT: Sure, may I know your travel dates?

USER: Thank you for your response, I want to take off on Aug 01 and book my return ticket also on Aug 03.

ASSISTANT: Do you have any specifications?

USER: I will prefer to travel in normal cost airline.

ASSISTANT: Please share me your name.

USER: Sure, my name is Charles Miller.

ASSISTANT: Sorry, there is no flight at this moment.

USER: That's ok, no problem.

ASSISTANT: Thank you.

USER: Thank you for your information.