You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am Nicholas Jones.

ASSISTANT: Ok.

USER: Can you please book a ticket for me as I am planning to go for hop-on hop-off tour at Houston, HOU?

ASSISTANT: Sure, please share your travel dates.

USER: Journey dates are 07/21 to 07/23.

ASSISTANT: May I know your source airport?

USER: Origin code is Washington, DCA.

ASSISTANT: Do you want connecting flight?

USER: I need connecting flight.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, there are no connecting flights available with your given details.

USER: No problem. Thank you.

ASSISTANT: Thank you for choosing us.