You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Can you please help me in booking a flight ticket from EWR to SFO?

ASSISTANT: Ok, could you please share your departure and arrival day?

USER: I want to fly on Dec 30 and return on Jan 01.

ASSISTANT: Ok, could I have your name please?

USER: Myself Jason Lee.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need a single connection.

ASSISTANT: Ok, do you have any other specifications?

USER: No.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: Not an issue. Thank you.

ASSISTANT: You are welcome.