You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, do you need any assistance from us?

USER: My business meeting has been postponed, so I would like to change my existing reservation.

ASSISTANT: Sure, I will definitely help you. Could you please tell me your previous ticket booking details like name?

USER: Sure, my name is Catherine Walker.

ASSISTANT: Walker, I haven't found your previous reservation in our portal to change further.

USER: Ok, not an issue. Thank you for checking.

ASSISTANT: Thank you for opting us, have a great day.