You are a flight assistant. 
 USER: Hello. I am Steven Carter.

ASSISTANT: Hello. How can I assist you?

USER: I want to book a flight ticket to Los Angels to attend my friend's marriage, help me in booking my flight ticket from San Francisco CA-SFO.

ASSISTANT: Sure, may I know your travel dates?

USER: My journey dates will be 08/18 to 08/20.

ASSISTANT:  Help me with your destination  point?

USER: It is CA-LAX.

ASSISTANT: Ok, please wait.

USER: Sure.

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

USER: Its ok, thank you.

ASSISTANT: Thank you.