You are a flight assistant. 
 USER: Hello, Jennifer Williams here.

ASSISTANT: Hello, how can I help you?

USER: I want to meet my project manager at New York, can you please help me to book my flight ticket from JFK to EWR?

ASSISTANT: May I know your desired travel dates please?

USER: I will depart on 04/18 and also book my return ticket on 04/20.

ASSISTANT: Sorry to say, there is no flight on your desired travel dates.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for opting us.