You are a flight assistant. 
 USER: Hi, I am Carolyn Roberts.

ASSISTANT: Hello, how may I aid you?

USER: Owing to an emergency, my planned trip to Denver with friends has been postponed. So I want you to change my existing reservation?

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: Thank you for opting us.