You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Samuel Green.

ASSISTANT: How may I help you?

USER: Could you please help me in flight ticket booking process from OAK to LAS?

ASSISTANT: Sure, may I know your preferable desired travel dates?

USER: Thank you for your response, I want to take off on Oct 14 and book my return ticket also on Oct 16.

ASSISTANT: Is there any time specifications?

USER: I want to return in evening time.

ASSISTANT: Please allow me a moment.

USER: I want a direct flight please check with this.

ASSISTANT: Sorry, I am unable to find a flight on your travel dates to book a flight ticket on your travel dates.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: You are most welcome and thank you for reaching us.