You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I am planning to celebrate my friend birthday party at San Francisco, CA-SFO can you help me booking a flight ticket from Houston, TX-IAH?

ASSISTANT: Ok, may I know your travel dates?

USER: I will start on 03/11 and return on 0/13.

ASSISTANT: Do you have any preference?

USER: I need a break in between my journey.

ASSISTANT: Ok, please wait I will revert you in a moment.

USER: Sure.

ASSISTANT:  Sorry, no flights are available on your travel dates.

USER: No problem.

ASSISTANT:  May I know your good name?

USER: Thank you for the information. I am Steven Scott.

ASSISTANT: Thank you for availing us.