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 Boston, BOS to San Francisco, SFO?

ASSISTANT: Sure, may I know your name?

USER: My name is Robert Hernandez.

ASSISTANT: Thank you. Can I know your travel dates?

USER: My journey dates are from Apr 18 to Apr 20.

ASSISTANT: Sure, do you have any class preference?

USER: I am ok with any class.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Flight-1029 having single connection is available with UA airlines and the ticket fare is 100 only. Flight will take-off at 20:00 hours and arrives at 22:00 hours. Can I book the ticket for you?

USER: Don't proceed for booking, I need a direct flight ticket.

ASSISTANT: Sorry, no direct flight available on your preferred travel dates.

USER: Ok, that's not a problem. Thanks for your information.

ASSISTANT: You are welcome and thank you for choosing us.