You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Helen Thomas. I want to book a ticket from EWR to ORD to meet my uncle, can you help me in booking?

ASSISTANT: Sure, can you please let me know your travel dates?

USER: I am departing on 08/23 and return on 08/25.

ASSISTANT: Sorry, no flights available on your given travel dates.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for choosing us.