You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am Paul Adams. Can you help me in booking my flight ticket from ORD to ATL?

ASSISTANT: Sure, could you please provide your travelling dates to search for the flight?

USER: My travelling dates will be Apr 7th to 9th.

ASSISTANT: May I know your airline preference please?

USER: I prefer a normal cost.

ASSISTANT: Sorry Paul, there is no flight found as per your travelling details.

USER: Thank ok.

ASSISTANT: Thank you for choosing us.

USER: Thank you.