You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Can you please help me to search a flight from San Francisco, CA-SFO?

ASSISTANT: May I know your destination airport code?

USER: Sure, the destination airport code is TX-IAH.

ASSISTANT: Please help me with your trip dates?

USER: The travelling dates are 02/25 to 02/27.

ASSISTANT: Sorry, there is no flight with your details.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us. May I know your name?

USER: My name is Daniel Harris. Thank you for your information.

ASSISTANT: Most welcome.