You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am John Thompson.

ASSISTANT: How can I aid you today?

USER: Can you help me in booking my flight ticket from HOU to SFO?

ASSISTANT: Sure, I will aid you with that. Could you please mention your preferable travel dates?

USER: My starting date is Aug 9th and return date is on Aug 11th.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Its ok, thank you.

ASSISTANT: Thank you for reaching us.

USER: Thank you.