You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I need you to book a flight ticket from MCO to SFO.

ASSISTANT: Sure, I am here to help you in booking. Can you please share your travel dates?

USER: April 19 and 21 are my planned travelling dates.

ASSISTANT: Ok, please mention your name.

USER: William Jones here.

ASSISTANT: May I know your departure time and arrival time?

USER: I wish to return in the afternoon.

ASSISTANT: Do you have any specification?

USER: I need a connecting flight.

ASSISTANT: Sorry, no flights are available on your preferable travel dates.

USER: That's ok. Thanks for your time.