You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: My name is Rachel Harris. I want to change an existing reservation.

ASSISTANT: Sure Harris. Please wait a minute.

USER: OK fine.

ASSISTANT: Thank you for waiting. Sorry for the inconvenience, there is no reservation found under your name.

USER: OK fine no issues.

ASSISTANT: Thank you for reaching us. Have a great day.

USER: Thank you.