You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you for the day?

USER: I want to change my reservation, can you help me with that?

ASSISTANT: Sure, can you please mention your name?

USER: Sure, David Martinez here.

ASSISTANT: We found reservation, with your name, can you please share your location codes?

USER: My airport codes are from IAD to OAK.

ASSISTANT: Can you please share your travelling dates?

USER: My travelling dates are from Aug 11-13.

ASSISTANT: Do you prefer class?

USER: I prefer business class.

ASSISTANT: Do you need connection limit?

USER: I need a connecting flight.

ASSISTANT: We found United Airline with fare 300 and flight number is 1014 with connecting flight. Shall I proceed with the booking?

USER: You can proceed with booking.

ASSISTANT: Your booking is done.

USER: Thank you for the help.

ASSISTANT: Thank you for choosing us.