You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: Can you help me to book a flight from SFO to IAH?

ASSISTANT: May I know on which dates you are willing to travel?

USER: My travelling dates are Nov 30 and Dec 02.

ASSISTANT: Do you have any other requirements to be met?

USER: I prefer direct flight.

ASSISTANT: Can I have your name please?

USER: My name is Raymond Adams.

ASSISTANT: Sorry to inform you that unfortunately there is no flights available by the given details.

USER: No issues, thank you for your time.

ASSISTANT: Thank you.