You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Please book me a flight ticket from DEN to LAX to meet my family.

ASSISTANT: Can I know your travelling dates?

USER: I have planned to travel on July 17th and return on July 19th.

ASSISTANT: Do you have any class preference?

USER: I am with any class.

ASSISTANT: Is there any connection limit?

USER: I prefer one connection limit.

ASSISTANT: Let me know your name.

USER: Myself Brandon Smith.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: Ok, no problem.

ASSISTANT: Thank you.

USER: Thank you.