You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Nicholas Hill. I would like to book a flight ticket from LAS to DEN to meet my friends. Could you please help me with booking a flight ticket?

ASSISTANT: Sure, I will help you. May I know your travelling dates?

USER: Sure my traveling dates are June 28 and June 30.

ASSISTANT: Do you have any connection limit/.

USER: Yes, I need a break in between the journey.

ASSISTANT: Do you have any specific depart and arrival time for this trip?

USER: I want to return in the evening.

ASSISTANT: Is there any other preferences?

USER: No , I do not have any other requirements.

ASSISTANT: Thanks for your details, there are no flights found on your data.

USER: No problem, thank you for your help.

ASSISTANT: Thank you.