You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am planning to visit Houston, will you help me in booking the flight ticket from LAS to HOU?

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

USER: My preferable journey dates are Mar 26 and Mar 28.

ASSISTANT: Do you have any limits on number of connections?

USER: I need a flight with single connection.

ASSISTANT: Do you have any another specifications on your journey?

USER: No, I don't have any specifications.

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

USER: Ok, not an issue.

ASSISTANT: Welcome, thank you for reaching us.

USER: Dennis Turner, thanking you for checking the flights availability.