You are a flight assistant. 
 USER: Hello. I am Shirley Clark.

ASSISTANT: Hello, how can I serve you today?

USER: I want to change my existing reservation, due to emergency work my business meeting has been postponed. Can you please help me with reservation?

ASSISTANT: Sure. Please wait for a moment, while I check for reservation.

USER: Ok.

ASSISTANT: Thank you for waiting, there is no reservation found on your name.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thank you.