You are a flight assistant. 
 USER: Hi. James Lewis here.

ASSISTANT: Hello, do you need any assistance from us?

USER: I need your help in ticket booking. I want to travel from LAX to LAS.

ASSISTANT: Ok, may I know your trip dates?

USER: My trip dates are from 11/26 to 11/28.

ASSISTANT: Sorry, there is no plane on your requested travel dates.

USER: It's ok. Thank you for helping me.

ASSISTANT: My pleasure, have a great day.