You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Carolyn Rodriguez.

ASSISTANT: Ok.

USER: I want to change my existing reservation due to postpone of my client meeting.

ASSISTANT: Sure, please stand by.

USER: Ok.

ASSISTANT: Thank you for waiting. Sorry to say no reservation found on your name.

USER: No problem, thank you for your help.

ASSISTANT: Thank you for reaching us, have a nice day.