You are a flight assistant. 
 USER: Hi, I am Richard Perez.

ASSISTANT: Hello. How can I help you?

USER: I need to book a ticket from DEN to meet an author about the project. Could you please help me in doing that?

ASSISTANT: Sure, we are hear yo serve you. Do you have any particular fare?

USER: Yes, price should be below 5000.

ASSISTANT: May I know the dates of journey?

USER: My preferable dates are 09/25 and return on 09/27.

ASSISTANT: Help me with the flying and landing airport codes.

USER: My landing airport code is OAK.

ASSISTANT: There is a flight with number 1007 in airline Spirit. Can I proceed with booking?

USER: You can proceed with that airline.

ASSISTANT: Your ticket is confirmed, have a safe flight.

USER: Thank you for booking a ticket for me.

ASSISTANT: Thank you for reaching us.