You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Can you please help me to book a flight from LAS to SFO?

ASSISTANT: Sure, may I know your travel dates?

USER: Sure, I want to travel on May 18 and need to return on May 20.

ASSISTANT: Do you have any specifications?

USER: I need a connecting flight.

ASSISTANT: Please share me your name.

USER: I am Robert Hill.

ASSISTANT: Flight-1020 is available with United airlines having single connection and the ticket costs you 100 only in economy class. Are you comfortable with this flight?

USER: Ok, please proceed.

ASSISTANT: Your ticket has been reserved.

USER: Thank you.

ASSISTANT: Thank you.