You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to book the flight ticket from BOS to LGA. Can you please help me?

ASSISTANT: Sure. Tell me your travel dates please?

USER: Dates are Aug 14 and Aug 16.

ASSISTANT: May I know your name please?

USER: Helen Lewis.

ASSISTANT: Are you looking for a stopover in your journey?

USER: Connected flight required.

ASSISTANT: Any other preferences?

USER: No.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: Thanks for waiting. But I am sorry to say that there are no flights available.

USER: Not an issue. Thanks for checking.

ASSISTANT: Thank you.