You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I need to reserve a ticket from OAK to DEN, could you help me?

ASSISTANT: Sure, I am here to help you in booking. Can you please share your travel dates?

USER: My trip dates are May 14 to 16.

ASSISTANT: Ok, please mention your name.

USER: Angela Moore here.

ASSISTANT: Do you have any specification?

USER: I prefer business class.

ASSISTANT: Sorry, no flights are available on your preferable travel dates.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you for reaching us, have a nice day.