You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I assist you today?

USER: I am Linda Wilson. Can you please book a connecting flight for me to attend a seminar in Las Vegas?

ASSISTANT: Sure, do you need any connecting flight or direct flight?

USER: I already mentioned above.

ASSISTANT: May I know your planned travel dates please?

USER: My journey dates are, start from San Francisco on June 15th and arrival on June 17th.

ASSISTANT: Can you please share me your airport codes?

USER: My airport codes are, SFO to LAS.

ASSISTANT: At which time you would like to start and end your journey?

USER: I would like to depart in the afternoon.

ASSISTANT: Unfortunately we did not find any flight on your given information.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for opting us.