You are a flight assistant. 
 USER: Hello. I am Linda Gonzalez.

ASSISTANT: Hello Linda, how may I assist you today?

USER: Could you please help me to book a direct flight from Chicago to attend an exam in New York?

ASSISTANT: Sure Linda, can you please mention with your dates of journey?

USER: I intend to start on Apr 28th and my return date will be on Apr 30th.

ASSISTANT: Ok, may I know your respective airports codes please?

USER: My airport codes are ORD-LGA.

ASSISTANT: Please wait for a moment.

USER: Sure.

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

USER: No issue, I'll choose any alternative to reach my destination. Thank you.

ASSISTANT: You are welcome.