You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you now?

USER: Owing to an emergency, my meeting with client got postponed. So I want you to change my existing reservation.

ASSISTANT: Sure, I am happy to help you with that. Can I have your good name please?

USER: Sure, Brenda Gonzalez here.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry Brenda Gonzalez, no reservation has found under your name to change.

USER: Ok, no issues. Thank you for your kind information.

ASSISTANT: Thank you for choosing us, have a good day.