You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you at this moment?

USER: Due to sudden change I want to change my existing reservation.

ASSISTANT: Sure, I am happy to help you.

USER: Please help me to find my reservation which has done on the name of Margaret Scott.

ASSISTANT: Ok, please wait for a moment. Thank you for your time in waiting. As per your request, there is no reservation found under name to modify it.

USER: Ok, thank you for checking.

ASSISTANT: Thank your for your valuable time in reaching us, have a great day.