You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I want to book a ticket from SFO to LAS. Could you book a ticket?

ASSISTANT: Sure, we are here to help you. Can you share me your travelling dates?

USER: Departure is on Feb, 11 and return date is Feb, 13.

ASSISTANT: May I know your name?

USER: My name is Charles Anderson.

ASSISTANT: Do you have any other specifications?

USER: I would prefer direct flight.

ASSISTANT: Ok, wait for some time.

USER: Sure.

ASSISTANT: Thanks for waiting there are no flights found on your details.

USER: Thank you.

ASSISTANT: Thanks for contacting us.