You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how can I help you?

USER: Please book a ticket from Dallas & Fort Worth, TX-DFW to San Francisco, CA-SFO.

ASSISTANT: Sure, may I know your journey dates please?

USER: Journey dates are from 05/31 to 06/02.

ASSISTANT: Can I have your good name please?

USER: I am Sharon Miller.

ASSISTANT: Unfortunately, there are no flights available on those dates Sharon.

USER: Thank you.

ASSISTANT: Thank you for choosing us.