You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello.

USER: My name is Samuel Wilson.

ASSISTANT:  What best I can do for you?

USER: As it's business trip, please book a ticket from Dallas & Fort Worth, TX-DFW to Oakland, CA-OAK.

ASSISTANT: We are happy to help you. May I know your travel dates?

USER: Departure is on 11/06 and return will be by 11/08.

ASSISTANT: Wait a moment please.

USER: Sure.

ASSISTANT:  Sorry to inform you that no flights are available on your preferred dates.

USER: Thanks for the help.

ASSISTANT: Thank you for reaching us.