You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I have planned to book a plane ticket from HOU to ORD, can you assist me in booking my ticket?

ASSISTANT: Sure, We are here to help you. Can I know your travelling dates?

USER: My preferred dates are May 20th and May 22nd.

ASSISTANT: Do you need any break?

USER: I need to travel in direct flight which must depart in morning time.

ASSISTANT: May I know your name?

USER: Mark Williams.

ASSISTANT: Is there any other specifications?

USER: No.

ASSISTANT:  We are unable to provide flight in between your journey routes due to some technical up-gradation at destination airport.

USER: No problem, thank you for searching.

ASSISTANT: Thank you for reaching us.