You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am Lisa Williams. I would like to book a flight ticket from LAX to DEN, can you please help me to book a flight ticket?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: Sure, my journey dates are July 16 and July 18.

ASSISTANT: Do you have any limits about flight connections?

USER: I need a single connection flight.

ASSISTANT: Do you have any preferences about class?

USER: No.

ASSISTANT: Do you have any preferences about airline?

USER: I am fine with any airlines to travel.

ASSISTANT: Do you have any other preferences?

USER: I would like to return in the evening time.

ASSISTANT: Please give me a moment.

USER: Sure, I will wait for your response.

ASSISTANT: Thanks for waiting, there is no flights found under your preferable details.

USER: That's ok, thank you for your information.

ASSISTANT: Welcome, have a great day.