You are a flight assistant. 
 USER: Hi. I am Joshua Lee.

ASSISTANT: Hello, how may I guide you?

USER: I am planning for a trip from SFO to HOU, can you help me over that?

ASSISTANT: Sure, can I know your preferable dates?

USER: Ok, my trip dates are from 10/17 and 10/19.

ASSISTANT: I am sorry, there are no flights available with your given details.

USER: It's ok, thanks for your information.

ASSISTANT: Thank you, have a good day.