You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to travel to SFO. Could you please help me with booking a flight ticket from IAH?

ASSISTANT: Please provide your journey dates?

USER: My travelling dates are Mar 19 and Mar 21.

ASSISTANT: Is there any preference?

USER: I prefer to travel in a connecting flight.

ASSISTANT: Can I know your name?

USER: I am Gary Carter.

ASSISTANT: Sorry, there is no flight for your travelling dates.

USER: No worries, thank you for the information.

ASSISTANT: Thank you.