You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am Jennifer Hernandez. Can you help me booking a flight ticket from IAH to LAS?

ASSISTANT: Sure, may I know your planned travel dates?

USER: I will start on Dec, 19 and return on Dec, 21.

ASSISTANT: Is there any class preference for you?

USER: No.

ASSISTANT: Do you have any specifications?

USER: I need to return in the evening.

ASSISTANT: May I know your connection limit?

USER: I need a break in my journey.

ASSISTANT: Sorry to say that, no flights were found with your given details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.