You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Cynthia Clark. I am planning to travel from DEN to HOU, can you help in booking a flight fro me?

ASSISTANT: May I know your desired travel dates please?

USER: My travelling dates are 08/18 to 08/20.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: Sorry to say, there is no flight ion your desired travel dates.

USER: That's ok, than you for your help.

ASSISTANT: Thank you for opting us.