You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, do you need any help from us?

USER: Jeffrey Phillips here. Please help me out in booking the ticket from DCA to BOS.

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

USER: My trip dates will be Dec 18 to Dec 20.

ASSISTANT: The economy class with flight number 1000 of Hawaiian airline is available having fare as 100 and connection as 1, is it ok for you?

USER: Can you please tell me return time?

ASSISTANT: Sure, the return time is in morning.

USER: I want return time must be in the evening.

ASSISTANT: Sorry, there is no flight with your request.

USER: That's ok. Thank you.

ASSISTANT: You are welcome.